mutter/gles/cogl.c

641 lines
14 KiB
C

/*
* Clutter COGL
*
* A basic GL/GLES Abstraction/Utility Layer
*
* Authored By Matthew Allum <mallum@openedhand.com>
*
* Copyright (C) 2007 OpenedHand
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "cogl.h"
#include <GLES/gl.h>
#include <string.h>
#include "cogl-internal.h"
#include "cogl-util.h"
#include "cogl-context.h"
/* GL error to string conversion */
#if COGL_DEBUG
struct token_string
{
GLuint Token;
const char *String;
};
static const struct token_string Errors[] = {
{ GL_NO_ERROR, "no error" },
{ GL_INVALID_ENUM, "invalid enumerant" },
{ GL_INVALID_VALUE, "invalid value" },
{ GL_INVALID_OPERATION, "invalid operation" },
{ GL_STACK_OVERFLOW, "stack overflow" },
{ GL_STACK_UNDERFLOW, "stack underflow" },
{ GL_OUT_OF_MEMORY, "out of memory" },
#ifdef GL_INVALID_FRAMEBUFFER_OPERATION_EXT
{ GL_INVALID_FRAMEBUFFER_OPERATION_EXT, "invalid framebuffer operation" },
#endif
{ ~0, NULL }
};
static const char*
error_string(GLenum errorCode)
{
int i;
for (i = 0; Errors[i].String; i++) {
if (Errors[i].Token == errorCode)
return Errors[i].String;
}
return "unknown";
}
#endif
CoglFuncPtr
cogl_get_proc_address (const gchar* name)
{
return NULL;
}
gboolean
cogl_check_extension (const gchar *name, const gchar *ext)
{
return FALSE;
}
void
cogl_paint_init (const ClutterColor *color)
{
#if COGL_DEBUG
fprintf(stderr, "\n ============== Paint Start ================ \n");
#endif
glClearColorx ((color->red << 16) / 0xff,
(color->green << 16) / 0xff,
(color->blue << 16) / 0xff,
0xff);
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
glDisable (GL_LIGHTING);
glDisable (GL_FOG);
}
/* FIXME: inline most of these */
void
cogl_push_matrix (void)
{
GE( glPushMatrix() );
}
void
cogl_pop_matrix (void)
{
GE( glPopMatrix() );
}
void
cogl_scale (ClutterFixed x, ClutterFixed y)
{
GE( glScalex (x, y, CFX_ONE) );
}
void
cogl_translatex (ClutterFixed x, ClutterFixed y, ClutterFixed z)
{
GE( glTranslatex (x, y, z) );
}
void
cogl_translate (gint x, gint y, gint z)
{
GE( glTranslatex (CLUTTER_INT_TO_FIXED(x),
CLUTTER_INT_TO_FIXED(y),
CLUTTER_INT_TO_FIXED(z)) );
}
void
cogl_rotatex (ClutterFixed angle,
ClutterFixed x,
ClutterFixed y,
ClutterFixed z)
{
GE( glRotatex (angle,x,y,z) );
}
void
cogl_rotate (gint angle, gint x, gint y, gint z)
{
GE( glRotatex (CLUTTER_INT_TO_FIXED(angle),
CLUTTER_INT_TO_FIXED(x),
CLUTTER_INT_TO_FIXED(y),
CLUTTER_INT_TO_FIXED(z)) );
}
static inline gboolean
cogl_toggle_flag (CoglContext *ctx,
gulong new_flags,
gulong flag,
GLenum gl_flag)
{
/* Toggles and caches a single enable flag on or off
* by comparing to current state
*/
if (new_flags & flag)
{
if (!(ctx->enable_flags & flag))
{
GE( glEnable (gl_flag) );
ctx->enable_flags |= flag;
return TRUE;
}
}
else if (ctx->enable_flags & flag)
{
GE( glDisable (gl_flag) );
ctx->enable_flags &= ~flag;
}
return FALSE;
}
static inline gboolean
cogl_toggle_client_flag (CoglContext *ctx,
gulong new_flags,
gulong flag,
GLenum gl_flag)
{
/* Toggles and caches a single client-side enable flag
* on or off by comparing to current state
*/
if (new_flags & flag)
{
if (!(ctx->enable_flags & flag))
{
GE( glEnableClientState (gl_flag) );
ctx->enable_flags |= flag;
return TRUE;
}
}
else if (ctx->enable_flags & flag)
{
GE( glDisableClientState (gl_flag) );
ctx->enable_flags &= ~flag;
}
return FALSE;
}
void
cogl_enable (gulong flags)
{
/* This function essentially caches glEnable state() in the
* hope of lessening number GL traffic.
*/
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (cogl_toggle_flag (ctx, flags,
COGL_ENABLE_BLEND,
GL_BLEND))
{
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
}
cogl_toggle_flag (ctx, flags,
COGL_ENABLE_TEXTURE_2D,
GL_TEXTURE_2D);
cogl_toggle_client_flag (ctx, flags,
COGL_ENABLE_VERTEX_ARRAY,
GL_VERTEX_ARRAY);
cogl_toggle_client_flag (ctx, flags,
COGL_ENABLE_TEXCOORD_ARRAY,
GL_TEXTURE_COORD_ARRAY);
cogl_toggle_client_flag (ctx, flags,
COGL_ENABLE_COLOR_ARRAY,
GL_COLOR_ARRAY);
}
gulong
cogl_get_enable ()
{
_COGL_GET_CONTEXT (ctx, 0);
return ctx->enable_flags;
}
void
cogl_enable_depth_test (gboolean setting)
{
if (setting)
{
glEnable (GL_DEPTH_TEST);
glEnable (GL_ALPHA_TEST);
glDepthFunc (GL_LEQUAL);
glAlphaFunc (GL_GREATER, 0.1);
}
else
{
glDisable (GL_DEPTH_TEST);
glDisable (GL_ALPHA_TEST);
}
}
void
cogl_color (const ClutterColor *color)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
#if 0 /*HAVE_GLES_COLOR4UB*/
/* NOTE: seems SDK_OGLES-1.1_LINUX_PCEMULATION_2.02.22.0756 has this call
* but is broken - see #857. Therefor disabling.
*/
/*
* GLES 1.1 does actually have this function, it's in the header file but
* missing in the reference manual (and SDK):
*
* http://www.khronos.org/egl/headers/1_1/gl.h
*/
GE( glColor4ub (color->red,
color->green,
color->blue,
color->alpha) );
#else
/* conversion can cause issues with picking on some gles implementations */
GE( glColor4x ((color->red << 16) / 0xff,
(color->green << 16) / 0xff,
(color->blue << 16) / 0xff,
(color->alpha << 16) / 0xff));
#endif
/* Store alpha for proper blending enables */
ctx->color_alpha = color->alpha;
}
void
cogl_clip_set (ClutterFixed x_offset,
ClutterFixed y_offset,
ClutterFixed width,
ClutterFixed height)
{
if (cogl_features_available (COGL_FEATURE_FOUR_CLIP_PLANES))
{
GLfixed eqn_left[4] = { CFX_ONE, 0, 0, -x_offset };
GLfixed eqn_right[4] = { -CFX_ONE, 0, 0, x_offset + width };
GLfixed eqn_top[4] = { 0, CFX_ONE, 0, -y_offset };
GLfixed eqn_bottom[4] = { 0, -CFX_ONE, 0, y_offset + height };
GE( glClipPlanex (GL_CLIP_PLANE0, eqn_left) );
GE( glClipPlanex (GL_CLIP_PLANE1, eqn_right) );
GE( glClipPlanex (GL_CLIP_PLANE2, eqn_top) );
GE( glClipPlanex (GL_CLIP_PLANE3, eqn_bottom) );
GE( glEnable (GL_CLIP_PLANE0) );
GE( glEnable (GL_CLIP_PLANE1) );
GE( glEnable (GL_CLIP_PLANE2) );
GE( glEnable (GL_CLIP_PLANE3) );
}
else if (cogl_features_available (COGL_FEATURE_STENCIL_BUFFER))
{
GE( glEnable (GL_STENCIL_TEST) );
GE( glClearStencil (0) );
GE( glClear (GL_STENCIL_BUFFER_BIT) );
GE( glStencilFunc (GL_NEVER, 0x1, 0x1) );
GE( glStencilOp (GL_INCR, GL_INCR, GL_INCR) );
GE( glColor4x (CFX_ONE, CFX_ONE, CFX_ONE, CFX_ONE ) );
cogl_fast_fill_rectanglex (x_offset, y_offset, width, height);
GE( glStencilFunc (GL_EQUAL, 0x1, 0x1) );
GE( glStencilOp (GL_KEEP, GL_KEEP, GL_KEEP) );
}
}
void
cogl_clip_unset (void)
{
if (cogl_features_available (COGL_FEATURE_FOUR_CLIP_PLANES))
{
GE( glDisable (GL_CLIP_PLANE3) );
GE( glDisable (GL_CLIP_PLANE2) );
GE( glDisable (GL_CLIP_PLANE1) );
GE( glDisable (GL_CLIP_PLANE0) );
}
else if (cogl_features_available (COGL_FEATURE_STENCIL_BUFFER))
{
GE( glDisable (GL_STENCIL_TEST) );
}
}
void
cogl_alpha_func (COGLenum func,
ClutterFixed ref)
{
GE( glAlphaFunc (func, CLUTTER_FIXED_TO_FLOAT(ref)) );
}
/*
* Fixed point implementation of the perspective function
*/
void
cogl_perspective (ClutterFixed fovy,
ClutterFixed aspect,
ClutterFixed zNear,
ClutterFixed zFar)
{
ClutterFixed xmax, ymax;
ClutterFixed x, y, c, d;
ClutterFixed fovy_rad_half = CFX_MUL (fovy, CFX_PI) / 360;
GLfixed m[16];
memset (&m[0], 0, sizeof (m));
/*
* 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 can are loosing significant
* precision, hence we use clutter_qmulx() here, not the fast macro.
*/
ymax = clutter_qmulx (zNear, CFX_DIV (clutter_sinx (fovy_rad_half),
clutter_cosx (fovy_rad_half)));
xmax = clutter_qmulx (ymax, aspect);
x = CFX_DIV (zNear, xmax);
y = CFX_DIV (zNear, ymax);
c = CFX_DIV (-(zFar + zNear), ( zFar - zNear));
d = CFX_DIV (-(clutter_qmulx (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 + ~CFX_ONE;
GE( glMultMatrixx (m) );
#undef M
}
void
cogl_setup_viewport (guint w,
guint h,
ClutterFixed fovy,
ClutterFixed aspect,
ClutterFixed z_near,
ClutterFixed z_far)
{
gint width = (gint) w;
gint height = (gint) h;
ClutterFixed z_camera;
GE( glViewport (0, 0, width, height) );
GE( glMatrixMode (GL_PROJECTION) );
GE( glLoadIdentity () );
/* For Ortho projection.
* glOrthox (0, width << 16, 0, height << 16, -1 << 16, 1 << 16);
*/
cogl_perspective (fovy, aspect, z_near, z_far);
GE( glMatrixMode (GL_MODELVIEW) );
GE( glLoadIdentity () );
/*
* camera distance from screen, 0.5 * tan (FOV)
*
* See comments in ../gl/cogl.c
*/
#define DEFAULT_Z_CAMERA 0.869f
z_camera = CLUTTER_FLOAT_TO_FIXED (DEFAULT_Z_CAMERA);
if (fovy != CFX_60)
{
ClutterFixed fovy_rad = CFX_MUL (fovy, CFX_PI) / 180;
z_camera = CFX_DIV (clutter_sinx (fovy_rad),
clutter_cosx (fovy_rad)) >> 1;
}
GE( glTranslatex (-1 << 15, -1 << 15, -z_camera));
GE( glScalex ( CFX_ONE / width,
-CFX_ONE / height,
CFX_ONE / width));
GE( glTranslatex (0, -CFX_ONE * height, 0) );
}
static void
_cogl_features_init ()
{
ClutterFeatureFlags flags = 0;
int stencil_bits = 0;
int max_clip_planes = 0;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
flags = COGL_FEATURE_TEXTURE_READ_PIXELS;
GE( glGetIntegerv (GL_STENCIL_BITS, &stencil_bits) );
if (stencil_bits > 0)
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;
ctx->feature_flags = flags;
ctx->features_cached = TRUE;
}
ClutterFeatureFlags
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 (ClutterFixed m[16])
{
glGetFixedv(GL_MODELVIEW_MATRIX, &m[0]);
}
void
cogl_get_projection_matrix (ClutterFixed m[16])
{
glGetFixedv(GL_PROJECTION_MATRIX, &m[0]);
}
void
cogl_get_viewport (ClutterFixed v[4])
{
glGetFixedv(GL_VIEWPORT, &v[0]);
}
void
cogl_get_bitmasks (gint *red, gint *green, gint *blue, gint *alpha)
{
if (red)
GE( glGetIntegerv(GL_RED_BITS, red) );
if (green)
GE( glGetIntegerv(GL_GREEN_BITS, green) );
if (blue)
GE( glGetIntegerv(GL_BLUE_BITS, blue) );
if (alpha)
GE( glGetIntegerv(GL_ALPHA_BITS, alpha ) );
}
void
cogl_fog_set (const ClutterColor *fog_color,
ClutterFixed density,
ClutterFixed z_near,
ClutterFixed z_far)
{
GLfixed fogColor[4];
fogColor[0] = (fog_color->red << 16) / 0xff;
fogColor[1] = (fog_color->green << 16) / 0xff;
fogColor[2] = (fog_color->blue << 16) / 0xff;
fogColor[3] = (fog_color->alpha << 16) / 0xff;
glEnable (GL_FOG);
glFogxv (GL_FOG_COLOR, fogColor);
glFogx (GL_FOG_MODE, GL_LINEAR);
glHint (GL_FOG_HINT, GL_NICEST);
glFogx (GL_FOG_DENSITY, (GLfixed) density);
glFogx (GL_FOG_START, (GLfixed) z_near);
glFogx (GL_FOG_END, (GLfixed) z_far);
}
/* Shaders, no support on regular OpenGL 1.1 */
COGLhandle
cogl_create_program (void)
{
return 0;
}
COGLhandle
cogl_create_shader (COGLenum shaderType)
{
return 0;
}
void
cogl_shader_source (COGLhandle shader,
const gchar *source)
{
}
void
cogl_shader_compile (COGLhandle shader_handle)
{
}
void
cogl_program_attach_shader (COGLhandle program_handle,
COGLhandle shader_handle)
{
}
void
cogl_program_link (COGLhandle program_handle)
{
}
void
cogl_program_use (COGLhandle program_handle)
{
}
COGLint
cogl_program_get_uniform_location (COGLhandle program_handle,
const gchar *uniform_name)
{
return 0;
}
void
cogl_program_destroy (COGLhandle handle)
{
}
void
cogl_shader_destroy (COGLhandle handle)
{
}
void
cogl_shader_get_info_log (COGLhandle handle,
guint size,
gchar *buffer)
{
}
void
cogl_shader_get_parameteriv (COGLhandle handle,
COGLenum pname,
COGLint *dest)
{
}
void
cogl_program_uniform_1f (COGLint uniform_no,
gfloat value)
{
}