43a5fef73d
All GL functions that are defined in a version later than 1.1 need to be called through cogl_get_proc_address because the Windows GL DLL does not export them to directly link against.
1207 lines
31 KiB
C
1207 lines
31 KiB
C
/*
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* Clutter COGL
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*
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* A basic GL/GLES Abstraction/Utility Layer
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*
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* Authored By Matthew Allum <mallum@openedhand.com>
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*
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* Copyright (C) 2007 OpenedHand
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the
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* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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* Boston, MA 02111-1307, USA.
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*/
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#ifdef HAVE_CONFIG_H
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#include "config.h"
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#endif
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#include "cogl.h"
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#include <string.h>
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#include <gmodule.h>
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#include <math.h>
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#include <stdlib.h>
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#ifdef HAVE_CLUTTER_GLX
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#include <dlfcn.h>
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#include <GL/glx.h>
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typedef CoglFuncPtr (*GLXGetProcAddressProc) (const guint8 *procName);
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#endif
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#include "cogl-internal.h"
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#include "cogl-util.h"
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#include "cogl-context.h"
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#if defined (HAVE_COGL_GLES2) || defined (HAVE_COGL_GLES)
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#include "cogl-gles2-wrapper.h"
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#endif
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/* GL error to string conversion */
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#if COGL_DEBUG
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struct token_string
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{
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GLuint Token;
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const char *String;
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};
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static const struct token_string Errors[] = {
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{ GL_NO_ERROR, "no error" },
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{ GL_INVALID_ENUM, "invalid enumerant" },
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{ GL_INVALID_VALUE, "invalid value" },
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{ GL_INVALID_OPERATION, "invalid operation" },
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{ GL_STACK_OVERFLOW, "stack overflow" },
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{ GL_STACK_UNDERFLOW, "stack underflow" },
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{ GL_OUT_OF_MEMORY, "out of memory" },
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#ifdef GL_INVALID_FRAMEBUFFER_OPERATION_EXT
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{ GL_INVALID_FRAMEBUFFER_OPERATION_EXT, "invalid framebuffer operation" },
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#endif
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{ ~0, NULL }
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};
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const char*
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_cogl_error_string(GLenum errorCode)
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{
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int i;
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for (i = 0; Errors[i].String; i++) {
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if (Errors[i].Token == errorCode)
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return Errors[i].String;
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}
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return "unknown";
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}
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#endif
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CoglFuncPtr
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cogl_get_proc_address (const gchar* name)
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{
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/* Sucks to ifdef here but not other option..? would be nice to
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* split the code up for more reuse (once more backends use this
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*/
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#if defined(HAVE_CLUTTER_GLX)
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static GLXGetProcAddressProc get_proc_func = NULL;
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static void *dlhand = NULL;
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if (get_proc_func == NULL && dlhand == NULL)
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{
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dlhand = dlopen (NULL, RTLD_LAZY);
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if (dlhand)
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{
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dlerror ();
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get_proc_func =
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(GLXGetProcAddressProc) dlsym (dlhand, "glXGetProcAddress");
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if (dlerror () != NULL)
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{
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get_proc_func =
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(GLXGetProcAddressProc) dlsym (dlhand, "glXGetProcAddressARB");
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}
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if (dlerror () != NULL)
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{
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get_proc_func = NULL;
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g_warning ("failed to bind GLXGetProcAddress "
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"or GLXGetProcAddressARB");
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}
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}
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}
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if (get_proc_func)
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return get_proc_func ((unsigned char*) name);
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#elif defined(HAVE_CLUTTER_WIN32)
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return (CoglFuncPtr) wglGetProcAddress ((LPCSTR) name);
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#else /* HAVE_CLUTTER_WIN32 */
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/* this should find the right function if the program is linked against a
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* library providing it */
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static GModule *module = NULL;
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if (module == NULL)
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module = g_module_open (NULL, G_MODULE_BIND_LAZY | G_MODULE_BIND_LOCAL);
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if (module)
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{
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gpointer symbol;
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if (g_module_symbol (module, name, &symbol))
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return symbol;
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}
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#endif /* HAVE_CLUTTER_WIN32 */
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return NULL;
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}
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gboolean
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cogl_check_extension (const gchar *name, const gchar *ext)
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{
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gchar *end;
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gint name_len, n;
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if (name == NULL || ext == NULL)
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return FALSE;
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end = (gchar*)(ext + strlen(ext));
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name_len = strlen(name);
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while (ext < end)
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{
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n = strcspn(ext, " ");
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if ((name_len == n) && (!strncmp(name, ext, n)))
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return TRUE;
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ext += (n + 1);
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}
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return FALSE;
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}
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void
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cogl_paint_init (const CoglColor *color)
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{
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#if COGL_DEBUG
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fprintf(stderr, "\n ============== Paint Start ================ \n");
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#endif
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GE( glClearColor (cogl_color_get_red_float (color),
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cogl_color_get_green_float (color),
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cogl_color_get_blue_float (color),
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0.0) );
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glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
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glDisable (GL_LIGHTING);
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glDisable (GL_FOG);
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/*
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* Disable the depth test for now as has some strange side effects,
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* mainly on x/y axis rotation with multiple layers at same depth
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* (eg rotating text on a bg has very strange effect). Seems no clean
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* 100% effective way to fix without other odd issues.. So for now
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* move to application to handle and add cogl_enable_depth_test()
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* as for custom actors (i.e groups) to enable if need be.
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*
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* glEnable (GL_DEPTH_TEST);
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* glEnable (GL_ALPHA_TEST)
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* glDepthFunc (GL_LEQUAL);
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* glAlphaFunc (GL_GREATER, 0.1);
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*/
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}
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/* FIXME: inline most of these */
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void
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cogl_push_matrix (void)
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{
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GE( glPushMatrix() );
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}
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void
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cogl_pop_matrix (void)
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{
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GE( glPopMatrix() );
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}
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void
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cogl_scale (float x, float y, float z)
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{
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GE( glScalef (x, y, z) );
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}
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void
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cogl_translate (float x, float y, float z)
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{
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GE( glTranslatef (x, y, z) );
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}
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void
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cogl_rotate (float angle, float x, float y, float z)
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{
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GE( glRotatef (angle, x, y, z) );
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}
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static inline gboolean
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cogl_toggle_flag (CoglContext *ctx,
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gulong new_flags,
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gulong flag,
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GLenum gl_flag)
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{
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/* Toggles and caches a single enable flag on or off
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* by comparing to current state
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*/
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if (new_flags & flag)
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{
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if (!(ctx->enable_flags & flag))
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{
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GE( glEnable (gl_flag) );
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ctx->enable_flags |= flag;
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return TRUE;
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}
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}
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else if (ctx->enable_flags & flag)
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{
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GE( glDisable (gl_flag) );
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ctx->enable_flags &= ~flag;
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}
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return FALSE;
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}
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static inline gboolean
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cogl_toggle_client_flag (CoglContext *ctx,
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gulong new_flags,
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gulong flag,
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GLenum gl_flag)
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{
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/* Toggles and caches a single client-side enable flag
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* on or off by comparing to current state
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*/
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if (new_flags & flag)
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{
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if (!(ctx->enable_flags & flag))
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{
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GE( glEnableClientState (gl_flag) );
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ctx->enable_flags |= flag;
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return TRUE;
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}
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}
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else if (ctx->enable_flags & flag)
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{
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GE( glDisableClientState (gl_flag) );
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ctx->enable_flags &= ~flag;
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}
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return FALSE;
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}
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void
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cogl_enable (gulong flags)
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{
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/* This function essentially caches glEnable state() in the
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* hope of lessening number GL traffic.
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*/
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_COGL_GET_CONTEXT (ctx, NO_RETVAL);
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cogl_toggle_flag (ctx, flags,
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COGL_ENABLE_BLEND,
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GL_BLEND);
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cogl_toggle_flag (ctx, flags,
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COGL_ENABLE_BACKFACE_CULLING,
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GL_CULL_FACE);
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cogl_toggle_client_flag (ctx, flags,
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COGL_ENABLE_VERTEX_ARRAY,
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GL_VERTEX_ARRAY);
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cogl_toggle_client_flag (ctx, flags,
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COGL_ENABLE_COLOR_ARRAY,
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GL_COLOR_ARRAY);
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}
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gulong
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cogl_get_enable ()
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{
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_COGL_GET_CONTEXT (ctx, 0);
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return ctx->enable_flags;
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}
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void
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cogl_enable_depth_test (gboolean setting)
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{
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if (setting)
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{
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glEnable (GL_DEPTH_TEST);
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glEnable (GL_ALPHA_TEST);
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glDepthFunc (GL_LEQUAL);
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glAlphaFunc (GL_GREATER, 0.1);
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}
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else
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{
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glDisable (GL_DEPTH_TEST);
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glDisable (GL_ALPHA_TEST);
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}
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}
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void
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cogl_enable_backface_culling (gboolean setting)
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{
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_COGL_GET_CONTEXT (ctx, NO_RETVAL);
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ctx->enable_backface_culling = setting;
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}
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void
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cogl_set_source_color (const CoglColor *color)
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{
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_COGL_GET_CONTEXT (ctx, NO_RETVAL);
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/* In case cogl_set_source_texture was previously used... */
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cogl_material_remove_layer (ctx->default_material, 0);
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cogl_material_set_color (ctx->default_material, color);
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cogl_set_source (ctx->default_material);
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}
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static void
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apply_matrix (const float *matrix, float *vertex)
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{
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int x, y;
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float vertex_out[4] = { 0 };
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for (y = 0; y < 4; y++)
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for (x = 0; x < 4; x++)
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vertex_out[y] += vertex[x] * matrix[y + x * 4];
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memcpy (vertex, vertex_out, sizeof (vertex_out));
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}
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static void
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project_vertex (float *modelview,
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float *project,
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float *vertex)
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{
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int i;
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/* Apply the modelview matrix */
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apply_matrix (modelview, vertex);
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/* Apply the projection matrix */
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apply_matrix (project, vertex);
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/* Convert from homogenized coordinates */
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for (i = 0; i < 4; i++)
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vertex[i] /= vertex[3];
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}
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static void
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set_clip_plane (GLint plane_num,
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const float *vertex_a,
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const float *vertex_b)
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{
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#if defined (HAVE_COGL_GLES2) || defined (HAVE_COGL_GLES)
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GLfloat plane[4];
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#else
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GLdouble plane[4];
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#endif
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GLfloat angle;
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_COGL_GET_CONTEXT (ctx, NO_RETVAL);
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/* Calculate the angle between the axes and the line crossing the
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two points */
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angle = atan2f (vertex_b[1] - vertex_a[1],
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vertex_b[0] - vertex_a[0]) * (180.0/G_PI);
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GE( glPushMatrix () );
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/* Load the identity matrix and multiply by the reverse of the
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projection matrix so we can specify the plane in screen
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coordinates */
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GE( glLoadIdentity () );
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GE( glMultMatrixf ((GLfloat *) ctx->inverse_projection) );
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/* Rotate about point a */
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GE( glTranslatef (vertex_a[0], vertex_a[1], vertex_a[2]) );
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/* Rotate the plane by the calculated angle so that it will connect
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the two points */
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GE( glRotatef (angle, 0.0f, 0.0f, 1.0f) );
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GE( glTranslatef (-vertex_a[0], -vertex_a[1], -vertex_a[2]) );
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plane[0] = 0;
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plane[1] = -1.0;
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plane[2] = 0;
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plane[3] = vertex_a[1];
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#if defined (HAVE_COGL_GLES2) || defined (HAVE_COGL_GLES)
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GE( glClipPlanef (plane_num, plane) );
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#else
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GE( glClipPlane (plane_num, plane) );
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#endif
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GE( glPopMatrix () );
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}
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void
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_cogl_set_clip_planes (float x_offset,
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float y_offset,
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float width,
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float height)
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{
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GLfloat modelview[16], projection[16];
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float vertex_tl[4] = { x_offset, y_offset, 0, 1.0 };
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float vertex_tr[4] = { x_offset + width, y_offset, 0, 1.0 };
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float vertex_bl[4] = { x_offset, y_offset + height, 0, 1.0 };
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float vertex_br[4] = { x_offset + width, y_offset + height,
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0, 1.0 };
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GE( glGetFloatv (GL_MODELVIEW_MATRIX, modelview) );
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GE( glGetFloatv (GL_PROJECTION_MATRIX, projection) );
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project_vertex (modelview, projection, vertex_tl);
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project_vertex (modelview, projection, vertex_tr);
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project_vertex (modelview, projection, vertex_bl);
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project_vertex (modelview, projection, vertex_br);
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/* If the order of the top and bottom lines is different from the
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order of the left and right lines then the clip rect must have
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been transformed so that the back is visible. We therefore need
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to swap one pair of vertices otherwise all of the planes will be
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the wrong way around */
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if ((vertex_tl[0] < vertex_tr[0] ? 1 : 0)
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!= (vertex_bl[1] < vertex_tl[1] ? 1 : 0))
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{
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float temp[4];
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memcpy (temp, vertex_tl, sizeof (temp));
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memcpy (vertex_tl, vertex_tr, sizeof (temp));
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memcpy (vertex_tr, temp, sizeof (temp));
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memcpy (temp, vertex_bl, sizeof (temp));
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memcpy (vertex_bl, vertex_br, sizeof (temp));
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memcpy (vertex_br, temp, sizeof (temp));
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}
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set_clip_plane (GL_CLIP_PLANE0, vertex_tl, vertex_tr);
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set_clip_plane (GL_CLIP_PLANE1, vertex_tr, vertex_br);
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set_clip_plane (GL_CLIP_PLANE2, vertex_br, vertex_bl);
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set_clip_plane (GL_CLIP_PLANE3, vertex_bl, vertex_tl);
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}
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|
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void
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_cogl_add_stencil_clip (float x_offset,
|
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float y_offset,
|
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float width,
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float height,
|
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gboolean first)
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{
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_COGL_GET_CONTEXT (ctx, NO_RETVAL);
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cogl_material_flush_gl_state (ctx->stencil_material, NULL);
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if (first)
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{
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GE( glEnable (GL_STENCIL_TEST) );
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|
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/* Initially disallow everything */
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GE( glClearStencil (0) );
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GE( glClear (GL_STENCIL_BUFFER_BIT) );
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|
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/* Punch out a hole to allow the rectangle */
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GE( glStencilFunc (GL_NEVER, 0x1, 0x1) );
|
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GE( glStencilOp (GL_REPLACE, GL_REPLACE, GL_REPLACE) );
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cogl_rectangle (x_offset, y_offset,
|
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x_offset + width, y_offset + height);
|
|
}
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|
else
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|
{
|
|
/* Add one to every pixel of the stencil buffer in the
|
|
rectangle */
|
|
GE( glStencilFunc (GL_NEVER, 0x1, 0x3) );
|
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GE( glStencilOp (GL_INCR, GL_INCR, GL_INCR) );
|
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cogl_rectangle (x_offset, y_offset,
|
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x_offset + width, y_offset + height);
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|
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/* Subtract one from all pixels in the stencil buffer so that
|
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only pixels where both the original stencil buffer and the
|
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rectangle are set will be valid */
|
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GE( glStencilOp (GL_DECR, GL_DECR, GL_DECR) );
|
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GE( glPushMatrix () );
|
|
GE( glLoadIdentity () );
|
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GE( glMatrixMode (GL_PROJECTION) );
|
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GE( glPushMatrix () );
|
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GE( glLoadIdentity () );
|
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cogl_rectangle (-1.0, -1.0, 1.0, 1.0);
|
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GE( glPopMatrix () );
|
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GE( glMatrixMode (GL_MODELVIEW) );
|
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GE( glPopMatrix () );
|
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}
|
|
|
|
/* Restore the stencil mode */
|
|
GE( glStencilFunc (GL_EQUAL, 0x1, 0x1) );
|
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GE( glStencilOp (GL_KEEP, GL_KEEP, GL_KEEP) );
|
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}
|
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|
|
void
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_cogl_set_matrix (const float *matrix)
|
|
{
|
|
GE( glLoadIdentity () );
|
|
GE( glMultMatrixf (matrix) );
|
|
}
|
|
|
|
void
|
|
_cogl_disable_stencil_buffer (void)
|
|
{
|
|
GE( glDisable (GL_STENCIL_TEST) );
|
|
}
|
|
|
|
void
|
|
_cogl_enable_clip_planes (void)
|
|
{
|
|
GE( glEnable (GL_CLIP_PLANE0) );
|
|
GE( glEnable (GL_CLIP_PLANE1) );
|
|
GE( glEnable (GL_CLIP_PLANE2) );
|
|
GE( glEnable (GL_CLIP_PLANE3) );
|
|
}
|
|
|
|
void
|
|
_cogl_disable_clip_planes (void)
|
|
{
|
|
GE( glDisable (GL_CLIP_PLANE3) );
|
|
GE( glDisable (GL_CLIP_PLANE2) );
|
|
GE( glDisable (GL_CLIP_PLANE1) );
|
|
GE( glDisable (GL_CLIP_PLANE0) );
|
|
}
|
|
|
|
void
|
|
cogl_perspective (float fovy,
|
|
float aspect,
|
|
float zNear,
|
|
float zFar)
|
|
{
|
|
float xmax, ymax;
|
|
float x, y, c, d;
|
|
float fovy_rad_half = (fovy * G_PI) / 360;
|
|
|
|
GLfloat m[16];
|
|
|
|
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
|
|
|
|
memset (&m[0], 0, sizeof (m));
|
|
|
|
GE( glMatrixMode (GL_PROJECTION) );
|
|
GE( glLoadIdentity () );
|
|
|
|
/*
|
|
* Based on the original algorithm in perspective():
|
|
*
|
|
* 1) xmin = -xmax => xmax + xmin == 0 && xmax - xmin == 2 * xmax
|
|
* same true for y, hence: a == 0 && b == 0;
|
|
*
|
|
* 2) When working with small numbers, we are loosing significant
|
|
* precision
|
|
*/
|
|
ymax = (zNear * (sinf (fovy_rad_half) / cosf (fovy_rad_half)));
|
|
xmax = (ymax * aspect);
|
|
|
|
x = (zNear / xmax);
|
|
y = (zNear / ymax);
|
|
c = (-(zFar + zNear) / ( zFar - zNear));
|
|
d = (-(2 * zFar) * zNear) / (zFar - zNear);
|
|
|
|
#define M(row,col) m[col*4+row]
|
|
M(0,0) = x;
|
|
M(1,1) = y;
|
|
M(2,2) = c;
|
|
M(2,3) = d;
|
|
M(3,2) = -1.0;
|
|
|
|
GE( glMultMatrixf (m) );
|
|
|
|
GE( glMatrixMode (GL_MODELVIEW) );
|
|
|
|
/* Calculate and store the inverse of the matrix */
|
|
memset (ctx->inverse_projection, 0, sizeof (float) * 16);
|
|
|
|
#define m ctx->inverse_projection
|
|
M(0, 0) = (1.0 / x);
|
|
M(1, 1) = (1.0 / y);
|
|
M(2, 3) = -1.0;
|
|
M(3, 2) = (1.0 / d);
|
|
M(3, 3) = (c / d);
|
|
#undef m
|
|
|
|
#undef M
|
|
}
|
|
|
|
void
|
|
cogl_frustum (float left,
|
|
float right,
|
|
float bottom,
|
|
float top,
|
|
float z_near,
|
|
float z_far)
|
|
{
|
|
float c, d;
|
|
|
|
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
|
|
|
|
GE( glMatrixMode (GL_PROJECTION) );
|
|
GE( glLoadIdentity () );
|
|
|
|
GE( glFrustum ((GLdouble)(left),
|
|
(GLdouble)(right),
|
|
(GLdouble)(bottom),
|
|
(GLdouble)(top),
|
|
(GLdouble)(z_near),
|
|
(GLdouble)(z_far)) );
|
|
|
|
GE( glMatrixMode (GL_MODELVIEW) );
|
|
|
|
/* Calculate and store the inverse of the matrix */
|
|
memset (ctx->inverse_projection, 0, sizeof (float) * 16);
|
|
|
|
c = - (z_far + z_near) / (z_far - z_near);
|
|
d = - (2 * (z_far * z_near)) / (z_far - z_near);
|
|
|
|
#define M(row,col) ctx->inverse_projection[col*4+row]
|
|
M(0,0) = (right - left) / (2 * z_near);
|
|
M(0,3) = (right + left) / (2 * z_near);
|
|
M(1,1) = (top - bottom) / (2 * z_near);
|
|
M(1,3) = (top + bottom) / (2 * z_near);
|
|
M(2,3) = -1.0;
|
|
M(3,2) = 1.0 / d;
|
|
M(3,3) = c / d;
|
|
#undef M
|
|
}
|
|
|
|
void
|
|
cogl_viewport (guint width,
|
|
guint height)
|
|
{
|
|
GE( glViewport (0, 0, width, height) );
|
|
}
|
|
|
|
void
|
|
cogl_setup_viewport (guint width,
|
|
guint height,
|
|
float fovy,
|
|
float aspect,
|
|
float z_near,
|
|
float z_far)
|
|
{
|
|
float z_camera;
|
|
float projection_matrix[16];
|
|
|
|
GE( glViewport (0, 0, width, height) );
|
|
|
|
/* For Ortho projection.
|
|
* glOrthof (0, width << 16, 0, height << 16, -1 << 16, 1 << 16);
|
|
*/
|
|
|
|
cogl_perspective (fovy, aspect, z_near, z_far);
|
|
|
|
/*
|
|
* In theory, we can compute the camera distance from screen as:
|
|
*
|
|
* 0.5 * tan (FOV)
|
|
*
|
|
* However, it's better to compute the z_camera from our projection
|
|
* matrix so that we get a 1:1 mapping at the screen distance. Consider
|
|
* the upper-left corner of the screen. It has object coordinates
|
|
* (0,0,0), so by the transform below, ends up with eye coordinate
|
|
*
|
|
* x_eye = x_object / width - 0.5 = - 0.5
|
|
* y_eye = (height - y_object) / width - 0.5 = 0.5
|
|
* z_eye = z_object / width - z_camera = - z_camera
|
|
*
|
|
* From cogl_perspective(), we know that the projection matrix has
|
|
* the form:
|
|
*
|
|
* (x, 0, 0, 0)
|
|
* (0, y, 0, 0)
|
|
* (0, 0, c, d)
|
|
* (0, 0, -1, 0)
|
|
*
|
|
* Applied to the above, we get clip coordinates of
|
|
*
|
|
* x_clip = x * (- 0.5)
|
|
* y_clip = y * 0.5
|
|
* w_clip = - 1 * (- z_camera) = z_camera
|
|
*
|
|
* Dividing through by w to get normalized device coordinates, we
|
|
* have, x_nd = x * 0.5 / z_camera, y_nd = - y * 0.5 / z_camera.
|
|
* The upper left corner of the screen has normalized device coordinates,
|
|
* (-1, 1), so to have the correct 1:1 mapping, we have to have:
|
|
*
|
|
* z_camera = 0.5 * x = 0.5 * y
|
|
*
|
|
* If x != y, then we have a non-uniform aspect ration, and a 1:1 mapping
|
|
* doesn't make sense.
|
|
*/
|
|
|
|
cogl_get_projection_matrix (projection_matrix);
|
|
z_camera = 0.5 * projection_matrix[0];
|
|
|
|
GE( glLoadIdentity () );
|
|
|
|
GE( glTranslatef (-0.5f, -0.5f, -z_camera) );
|
|
GE( glScalef (1.0f / width, -1.0f / height, 1.0f / width) );
|
|
GE( glTranslatef (0.0f, -1.0 * height, 0.0f) );
|
|
}
|
|
|
|
#ifdef HAVE_CLUTTER_OSX
|
|
static gboolean
|
|
really_enable_npot (void)
|
|
{
|
|
/* OSX backend + ATI Radeon X1600 + NPOT texture + GL_REPEAT seems to crash
|
|
* http://bugzilla.openedhand.com/show_bug.cgi?id=929
|
|
*
|
|
* Temporary workaround until post 0.8 we rejig the features set up a
|
|
* little to allow the backend to overide.
|
|
*/
|
|
const char *gl_renderer;
|
|
const char *env_string;
|
|
|
|
/* Regardless of hardware, allow user to decide. */
|
|
env_string = g_getenv ("COGL_ENABLE_NPOT");
|
|
if (env_string != NULL)
|
|
return env_string[0] == '1';
|
|
|
|
gl_renderer = (char*)glGetString (GL_RENDERER);
|
|
if (strstr (gl_renderer, "ATI Radeon X1600") != NULL)
|
|
return FALSE;
|
|
|
|
return TRUE;
|
|
}
|
|
#endif
|
|
|
|
static void
|
|
_cogl_features_init ()
|
|
{
|
|
CoglFeatureFlags flags = 0;
|
|
const gchar *gl_extensions;
|
|
GLint max_clip_planes = 0;
|
|
GLint num_stencil_bits = 0;
|
|
|
|
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
|
|
|
|
flags = COGL_FEATURE_TEXTURE_READ_PIXELS;
|
|
|
|
gl_extensions = (const gchar*) glGetString (GL_EXTENSIONS);
|
|
|
|
if (cogl_check_extension ("GL_ARB_texture_non_power_of_two", gl_extensions))
|
|
{
|
|
#ifdef HAVE_CLUTTER_OSX
|
|
if (really_enable_npot ())
|
|
#endif
|
|
flags |= COGL_FEATURE_TEXTURE_NPOT;
|
|
}
|
|
|
|
#ifdef GL_YCBCR_MESA
|
|
if (cogl_check_extension ("GL_MESA_ycbcr_texture", gl_extensions))
|
|
{
|
|
flags |= COGL_FEATURE_TEXTURE_YUV;
|
|
}
|
|
#endif
|
|
|
|
if (cogl_check_extension ("GL_ARB_shader_objects", gl_extensions) &&
|
|
cogl_check_extension ("GL_ARB_vertex_shader", gl_extensions) &&
|
|
cogl_check_extension ("GL_ARB_fragment_shader", gl_extensions))
|
|
{
|
|
ctx->pf_glCreateProgramObjectARB =
|
|
(COGL_PFNGLCREATEPROGRAMOBJECTARBPROC)
|
|
cogl_get_proc_address ("glCreateProgramObjectARB");
|
|
|
|
ctx->pf_glCreateShaderObjectARB =
|
|
(COGL_PFNGLCREATESHADEROBJECTARBPROC)
|
|
cogl_get_proc_address ("glCreateShaderObjectARB");
|
|
|
|
ctx->pf_glShaderSourceARB =
|
|
(COGL_PFNGLSHADERSOURCEARBPROC)
|
|
cogl_get_proc_address ("glShaderSourceARB");
|
|
|
|
ctx->pf_glCompileShaderARB =
|
|
(COGL_PFNGLCOMPILESHADERARBPROC)
|
|
cogl_get_proc_address ("glCompileShaderARB");
|
|
|
|
ctx->pf_glAttachObjectARB =
|
|
(COGL_PFNGLATTACHOBJECTARBPROC)
|
|
cogl_get_proc_address ("glAttachObjectARB");
|
|
|
|
ctx->pf_glLinkProgramARB =
|
|
(COGL_PFNGLLINKPROGRAMARBPROC)
|
|
cogl_get_proc_address ("glLinkProgramARB");
|
|
|
|
ctx->pf_glUseProgramObjectARB =
|
|
(COGL_PFNGLUSEPROGRAMOBJECTARBPROC)
|
|
cogl_get_proc_address ("glUseProgramObjectARB");
|
|
|
|
ctx->pf_glGetUniformLocationARB =
|
|
(COGL_PFNGLGETUNIFORMLOCATIONARBPROC)
|
|
cogl_get_proc_address ("glGetUniformLocationARB");
|
|
|
|
ctx->pf_glDeleteObjectARB =
|
|
(COGL_PFNGLDELETEOBJECTARBPROC)
|
|
cogl_get_proc_address ("glDeleteObjectARB");
|
|
|
|
ctx->pf_glGetInfoLogARB =
|
|
(COGL_PFNGLGETINFOLOGARBPROC)
|
|
cogl_get_proc_address ("glGetInfoLogARB");
|
|
|
|
ctx->pf_glGetObjectParameterivARB =
|
|
(COGL_PFNGLGETOBJECTPARAMETERIVARBPROC)
|
|
cogl_get_proc_address ("glGetObjectParameterivARB");
|
|
|
|
ctx->pf_glUniform1fARB =
|
|
(COGL_PFNGLUNIFORM1FARBPROC)
|
|
cogl_get_proc_address ("glUniform1fARB");
|
|
|
|
ctx->pf_glVertexAttribPointerARB =
|
|
(COGL_PFNGLVERTEXATTRIBPOINTERARBPROC)
|
|
cogl_get_proc_address ("glVertexAttribPointerARB");
|
|
|
|
ctx->pf_glEnableVertexAttribArrayARB =
|
|
(COGL_PFNGLENABLEVERTEXATTRIBARRAYARBPROC)
|
|
cogl_get_proc_address ("glEnableVertexAttribArrayARB");
|
|
|
|
ctx->pf_glDisableVertexAttribArrayARB =
|
|
(COGL_PFNGLDISABLEVERTEXATTRIBARRAYARBPROC)
|
|
cogl_get_proc_address ("glDisableVertexAttribArrayARB");
|
|
|
|
ctx->pf_glUniform2fARB =
|
|
(COGL_PFNGLUNIFORM2FARBPROC)
|
|
cogl_get_proc_address ("glUniform2fARB");
|
|
|
|
ctx->pf_glUniform3fARB =
|
|
(COGL_PFNGLUNIFORM3FARBPROC)
|
|
cogl_get_proc_address ("glUniform3fARB");
|
|
|
|
ctx->pf_glUniform4fARB =
|
|
(COGL_PFNGLUNIFORM4FARBPROC)
|
|
cogl_get_proc_address ("glUniform4fARB");
|
|
|
|
ctx->pf_glUniform1fvARB =
|
|
(COGL_PFNGLUNIFORM1FVARBPROC)
|
|
cogl_get_proc_address ("glUniform1fvARB");
|
|
|
|
ctx->pf_glUniform2fvARB =
|
|
(COGL_PFNGLUNIFORM2FVARBPROC)
|
|
cogl_get_proc_address ("glUniform2fvARB");
|
|
|
|
ctx->pf_glUniform3fvARB =
|
|
(COGL_PFNGLUNIFORM3FVARBPROC)
|
|
cogl_get_proc_address ("glUniform3fvARB");
|
|
|
|
ctx->pf_glUniform4fvARB =
|
|
(COGL_PFNGLUNIFORM4FVARBPROC)
|
|
cogl_get_proc_address ("glUniform4fvARB");
|
|
|
|
ctx->pf_glUniform1iARB =
|
|
(COGL_PFNGLUNIFORM1IARBPROC)
|
|
cogl_get_proc_address ("glUniform1iARB");
|
|
|
|
ctx->pf_glUniform2iARB =
|
|
(COGL_PFNGLUNIFORM2IARBPROC)
|
|
cogl_get_proc_address ("glUniform2iARB");
|
|
|
|
ctx->pf_glUniform3iARB =
|
|
(COGL_PFNGLUNIFORM3IARBPROC)
|
|
cogl_get_proc_address ("glUniform3iARB");
|
|
|
|
ctx->pf_glUniform4iARB =
|
|
(COGL_PFNGLUNIFORM4IARBPROC)
|
|
cogl_get_proc_address ("glUniform4iARB");
|
|
|
|
ctx->pf_glUniform1ivARB =
|
|
(COGL_PFNGLUNIFORM1IVARBPROC)
|
|
cogl_get_proc_address ("glUniform1ivARB");
|
|
|
|
ctx->pf_glUniform2ivARB =
|
|
(COGL_PFNGLUNIFORM2IVARBPROC)
|
|
cogl_get_proc_address ("glUniform2ivARB");
|
|
|
|
ctx->pf_glUniform3ivARB =
|
|
(COGL_PFNGLUNIFORM3IVARBPROC)
|
|
cogl_get_proc_address ("glUniform3ivARB");
|
|
|
|
ctx->pf_glUniform4ivARB =
|
|
(COGL_PFNGLUNIFORM4IVARBPROC)
|
|
cogl_get_proc_address ("glUniform4ivARB");
|
|
|
|
ctx->pf_glUniformMatrix2fvARB =
|
|
(COGL_PFNGLUNIFORMMATRIX2FVARBPROC)
|
|
cogl_get_proc_address ("glUniformMatrix2fvARB");
|
|
|
|
ctx->pf_glUniformMatrix3fvARB =
|
|
(COGL_PFNGLUNIFORMMATRIX3FVARBPROC)
|
|
cogl_get_proc_address ("glUniformMatrix3fvARB");
|
|
|
|
ctx->pf_glUniformMatrix4fvARB =
|
|
(COGL_PFNGLUNIFORMMATRIX4FVARBPROC)
|
|
cogl_get_proc_address ("glUniformMatrix4fvARB");
|
|
|
|
if (ctx->pf_glCreateProgramObjectARB &&
|
|
ctx->pf_glCreateShaderObjectARB &&
|
|
ctx->pf_glShaderSourceARB &&
|
|
ctx->pf_glCompileShaderARB &&
|
|
ctx->pf_glAttachObjectARB &&
|
|
ctx->pf_glLinkProgramARB &&
|
|
ctx->pf_glUseProgramObjectARB &&
|
|
ctx->pf_glGetUniformLocationARB &&
|
|
ctx->pf_glDeleteObjectARB &&
|
|
ctx->pf_glGetInfoLogARB &&
|
|
ctx->pf_glGetObjectParameterivARB &&
|
|
ctx->pf_glUniform1fARB &&
|
|
ctx->pf_glUniform2fARB &&
|
|
ctx->pf_glUniform3fARB &&
|
|
ctx->pf_glUniform4fARB &&
|
|
ctx->pf_glUniform1fvARB &&
|
|
ctx->pf_glUniform2fvARB &&
|
|
ctx->pf_glUniform3fvARB &&
|
|
ctx->pf_glUniform4fvARB &&
|
|
ctx->pf_glUniform1iARB &&
|
|
ctx->pf_glUniform2iARB &&
|
|
ctx->pf_glUniform3iARB &&
|
|
ctx->pf_glUniform4iARB &&
|
|
ctx->pf_glUniform1ivARB &&
|
|
ctx->pf_glUniform2ivARB &&
|
|
ctx->pf_glUniform3ivARB &&
|
|
ctx->pf_glUniform4ivARB &&
|
|
ctx->pf_glUniformMatrix2fvARB &&
|
|
ctx->pf_glUniformMatrix3fvARB &&
|
|
ctx->pf_glUniformMatrix4fvARB &&
|
|
ctx->pf_glVertexAttribPointerARB &&
|
|
ctx->pf_glEnableVertexAttribArrayARB &&
|
|
ctx->pf_glDisableVertexAttribArrayARB)
|
|
flags |= COGL_FEATURE_SHADERS_GLSL;
|
|
}
|
|
|
|
if (cogl_check_extension ("GL_EXT_framebuffer_object", gl_extensions) ||
|
|
cogl_check_extension ("GL_ARB_framebuffer_object", gl_extensions))
|
|
{
|
|
ctx->pf_glGenRenderbuffersEXT =
|
|
(COGL_PFNGLGENRENDERBUFFERSEXTPROC)
|
|
cogl_get_proc_address ("glGenRenderbuffersEXT");
|
|
|
|
ctx->pf_glDeleteRenderbuffersEXT =
|
|
(COGL_PFNGLDELETERENDERBUFFERSEXTPROC)
|
|
cogl_get_proc_address ("glDeleteRenderbuffersEXT");
|
|
|
|
ctx->pf_glBindRenderbufferEXT =
|
|
(COGL_PFNGLBINDRENDERBUFFEREXTPROC)
|
|
cogl_get_proc_address ("glBindRenderbufferEXT");
|
|
|
|
ctx->pf_glRenderbufferStorageEXT =
|
|
(COGL_PFNGLRENDERBUFFERSTORAGEEXTPROC)
|
|
cogl_get_proc_address ("glRenderbufferStorageEXT");
|
|
|
|
ctx->pf_glGenFramebuffersEXT =
|
|
(COGL_PFNGLGENFRAMEBUFFERSEXTPROC)
|
|
cogl_get_proc_address ("glGenFramebuffersEXT");
|
|
|
|
ctx->pf_glBindFramebufferEXT =
|
|
(COGL_PFNGLBINDFRAMEBUFFEREXTPROC)
|
|
cogl_get_proc_address ("glBindFramebufferEXT");
|
|
|
|
ctx->pf_glFramebufferTexture2DEXT =
|
|
(COGL_PFNGLFRAMEBUFFERTEXTURE2DEXTPROC)
|
|
cogl_get_proc_address ("glFramebufferTexture2DEXT");
|
|
|
|
ctx->pf_glFramebufferRenderbufferEXT =
|
|
(COGL_PFNGLFRAMEBUFFERRENDERBUFFEREXTPROC)
|
|
cogl_get_proc_address ("glFramebufferRenderbufferEXT");
|
|
|
|
ctx->pf_glCheckFramebufferStatusEXT =
|
|
(COGL_PFNGLCHECKFRAMEBUFFERSTATUSEXTPROC)
|
|
cogl_get_proc_address ("glCheckFramebufferStatusEXT");
|
|
|
|
ctx->pf_glDeleteFramebuffersEXT =
|
|
(COGL_PFNGLDELETEFRAMEBUFFERSEXTPROC)
|
|
cogl_get_proc_address ("glDeleteFramebuffersEXT");
|
|
|
|
if (ctx->pf_glGenRenderbuffersEXT &&
|
|
ctx->pf_glBindRenderbufferEXT &&
|
|
ctx->pf_glRenderbufferStorageEXT &&
|
|
ctx->pf_glGenFramebuffersEXT &&
|
|
ctx->pf_glBindFramebufferEXT &&
|
|
ctx->pf_glFramebufferTexture2DEXT &&
|
|
ctx->pf_glFramebufferRenderbufferEXT &&
|
|
ctx->pf_glCheckFramebufferStatusEXT &&
|
|
ctx->pf_glDeleteFramebuffersEXT)
|
|
flags |= COGL_FEATURE_OFFSCREEN;
|
|
}
|
|
|
|
if (cogl_check_extension ("GL_EXT_framebuffer_blit", gl_extensions))
|
|
{
|
|
ctx->pf_glBlitFramebufferEXT =
|
|
(COGL_PFNGLBLITFRAMEBUFFEREXTPROC)
|
|
cogl_get_proc_address ("glBlitFramebufferEXT");
|
|
|
|
if (ctx->pf_glBlitFramebufferEXT)
|
|
flags |= COGL_FEATURE_OFFSCREEN_BLIT;
|
|
}
|
|
|
|
if (cogl_check_extension ("GL_EXT_framebuffer_multisample", gl_extensions))
|
|
{
|
|
ctx->pf_glRenderbufferStorageMultisampleEXT =
|
|
(COGL_PFNGLRENDERBUFFERSTORAGEMULTISAMPLEEXTPROC)
|
|
cogl_get_proc_address ("glRenderbufferStorageMultisampleEXT");
|
|
|
|
if (ctx->pf_glRenderbufferStorageMultisampleEXT)
|
|
flags |= COGL_FEATURE_OFFSCREEN_MULTISAMPLE;
|
|
}
|
|
|
|
GE( glGetIntegerv (GL_STENCIL_BITS, &num_stencil_bits) );
|
|
/* We need at least three stencil bits to combine clips */
|
|
if (num_stencil_bits > 2)
|
|
flags |= COGL_FEATURE_STENCIL_BUFFER;
|
|
|
|
GE( glGetIntegerv (GL_MAX_CLIP_PLANES, &max_clip_planes) );
|
|
if (max_clip_planes >= 4)
|
|
flags |= COGL_FEATURE_FOUR_CLIP_PLANES;
|
|
|
|
if (cogl_check_extension ("GL_ARB_vertex_buffer_object", gl_extensions))
|
|
{
|
|
ctx->pf_glGenBuffersARB =
|
|
(COGL_PFNGLGENBUFFERSARBPROC)
|
|
cogl_get_proc_address ("glGenBuffersARB");
|
|
ctx->pf_glBindBufferARB =
|
|
(COGL_PFNGLBINDBUFFERARBPROC)
|
|
cogl_get_proc_address ("glBindBufferARB");
|
|
ctx->pf_glBufferDataARB =
|
|
(COGL_PFNGLBUFFERDATAARBPROC)
|
|
cogl_get_proc_address ("glBufferDataARB");
|
|
ctx->pf_glBufferSubDataARB =
|
|
(COGL_PFNGLBUFFERSUBDATAARBPROC)
|
|
cogl_get_proc_address ("glBufferSubDataARB");
|
|
ctx->pf_glDeleteBuffersARB =
|
|
(COGL_PFNGLDELETEBUFFERSARBPROC)
|
|
cogl_get_proc_address ("glDeleteBuffersARB");
|
|
ctx->pf_glMapBufferARB =
|
|
(COGL_PFNGLMAPBUFFERARBPROC)
|
|
cogl_get_proc_address ("glMapBufferARB");
|
|
ctx->pf_glUnmapBufferARB =
|
|
(COGL_PFNGLUNMAPBUFFERARBPROC)
|
|
cogl_get_proc_address ("glUnmapBufferARB");
|
|
if (ctx->pf_glGenBuffersARB
|
|
&& ctx->pf_glBindBufferARB
|
|
&& ctx->pf_glBufferDataARB
|
|
&& ctx->pf_glBufferSubDataARB
|
|
&& ctx->pf_glDeleteBuffersARB
|
|
&& ctx->pf_glMapBufferARB
|
|
&& ctx->pf_glUnmapBufferARB)
|
|
flags |= COGL_FEATURE_VBOS;
|
|
}
|
|
|
|
/* These should always be available because they are defined in GL
|
|
1.2, but we can't call it directly because under Windows
|
|
functions > 1.1 aren't exported */
|
|
ctx->pf_glDrawRangeElements =
|
|
(COGL_PFNGLDRAWRANGEELEMENTSPROC)
|
|
cogl_get_proc_address ("glDrawRangeElements");
|
|
ctx->pf_glActiveTexture =
|
|
(COGL_PFNGLACTIVETEXTUREPROC)
|
|
cogl_get_proc_address ("glActiveTexture");
|
|
ctx->pf_glClientActiveTexture =
|
|
(COGL_PFNGLCLIENTACTIVETEXTUREPROC)
|
|
cogl_get_proc_address ("glClientActiveTexture");
|
|
|
|
/* Cache features */
|
|
ctx->feature_flags = flags;
|
|
ctx->features_cached = TRUE;
|
|
}
|
|
|
|
CoglFeatureFlags
|
|
cogl_get_features ()
|
|
{
|
|
_COGL_GET_CONTEXT (ctx, 0);
|
|
|
|
if (!ctx->features_cached)
|
|
_cogl_features_init ();
|
|
|
|
return ctx->feature_flags;
|
|
}
|
|
|
|
gboolean
|
|
cogl_features_available (CoglFeatureFlags features)
|
|
{
|
|
_COGL_GET_CONTEXT (ctx, 0);
|
|
|
|
if (!ctx->features_cached)
|
|
_cogl_features_init ();
|
|
|
|
return (ctx->feature_flags & features) == features;
|
|
}
|
|
|
|
void
|
|
cogl_get_modelview_matrix (float m[16])
|
|
{
|
|
glGetFloatv (GL_MODELVIEW_MATRIX, m);
|
|
}
|
|
|
|
void
|
|
cogl_get_projection_matrix (float m[16])
|
|
{
|
|
glGetFloatv (GL_PROJECTION_MATRIX, m);
|
|
}
|
|
|
|
void
|
|
cogl_get_viewport (float v[4])
|
|
{
|
|
/* FIXME: cogl_get_viewport should return a gint vec */
|
|
#if defined (HAVE_COGL_GLES2) || defined (HAVE_COGL_GLES)
|
|
GLint viewport[4];
|
|
int i;
|
|
|
|
glGetIntegerv (GL_VIEWPORT, viewport);
|
|
|
|
for (i = 0; i < 4; i++)
|
|
v[i] = (float)(viewport[i]);
|
|
#else
|
|
glGetFloatv (GL_VIEWPORT, v);
|
|
#endif
|
|
}
|
|
|
|
void
|
|
cogl_get_bitmasks (gint *red, gint *green, gint *blue, gint *alpha)
|
|
{
|
|
GLint value;
|
|
if (red)
|
|
{
|
|
GE( glGetIntegerv(GL_RED_BITS, &value) );
|
|
*red = value;
|
|
}
|
|
if (green)
|
|
{
|
|
GE( glGetIntegerv(GL_GREEN_BITS, &value) );
|
|
*green = value;
|
|
}
|
|
if (blue)
|
|
{
|
|
GE( glGetIntegerv(GL_BLUE_BITS, &value) );
|
|
*blue = value;
|
|
}
|
|
if (alpha)
|
|
{
|
|
GE( glGetIntegerv(GL_ALPHA_BITS, &value ) );
|
|
*alpha = value;
|
|
}
|
|
}
|
|
|
|
void
|
|
cogl_set_fog (const CoglColor *fog_color,
|
|
float density,
|
|
float z_near,
|
|
float z_far)
|
|
{
|
|
GLfloat fogColor[4];
|
|
|
|
fogColor[0] = cogl_color_get_red_float (fog_color);
|
|
fogColor[1] = cogl_color_get_green_float (fog_color);
|
|
fogColor[2] = cogl_color_get_blue_float (fog_color);
|
|
fogColor[3] = cogl_color_get_alpha_float (fog_color);
|
|
|
|
glEnable (GL_FOG);
|
|
|
|
glFogfv (GL_FOG_COLOR, fogColor);
|
|
|
|
/* NB: GLES doesn't have glFogi */
|
|
glFogf (GL_FOG_MODE, GL_LINEAR);
|
|
glHint (GL_FOG_HINT, GL_NICEST);
|
|
|
|
glFogf (GL_FOG_DENSITY, (GLfloat) density);
|
|
glFogf (GL_FOG_START, (GLfloat) z_near);
|
|
glFogf (GL_FOG_END, (GLfloat) z_far);
|
|
}
|
|
|