b2e735ff7f
The GL or GLES library is now dynamically loaded by the CoglRenderer so that it can choose between GL, GLES1 and GLES2 at runtime. The library is loaded by the renderer because it needs to be done before calling eglInitialize. There is a new environment variable called COGL_DRIVER to choose between gl, gles1 or gles2. The #ifdefs for HAVE_COGL_GL, HAVE_COGL_GLES and HAVE_COGL_GLES2 have been changed so that they don't assume the ifdefs are mutually exclusive. They haven't been removed entirely so that it's possible to compile the GLES backends without the the enums from the GL headers. When using GLX the winsys additionally dynamically loads libGL because that also contains the GLX API. It can't be linked in directly because that would probably conflict with the GLES API if the EGL is selected. When compiling with EGL support the library links directly to libEGL because it doesn't contain any GL API so it shouldn't have any conflicts. When building for WGL or OSX Cogl still directly links against the GL API so there is a #define in config.h so that Cogl won't try to dlopen the library. Cogl-pango previously had a #ifdef to detect when the GL backend is used so that it can sneakily pass GL_QUADS to cogl_vertex_buffer_draw. This is now changed so that it queries the CoglContext for the backend. However to get this to work Cogl now needs to export the _cogl_context_get_default symbol and cogl-pango needs some extra -I flags to so that it can include cogl-context-private.h
764 lines
23 KiB
C
764 lines
23 KiB
C
/*
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* Cogl
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*
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* An object oriented GL/GLES Abstraction/Utility Layer
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*
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* Copyright (C) 2007,2008,2009,2010 Intel Corporation.
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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, see <http://www.gnu.org/licenses/>.
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*
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*
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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 <string.h>
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#include <math.h>
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#include <glib.h>
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#include "cogl.h"
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#include "cogl-clip-stack.h"
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#include "cogl-primitives.h"
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#include "cogl-context-private.h"
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#include "cogl-internal.h"
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#include "cogl-framebuffer-private.h"
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#include "cogl-journal-private.h"
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#include "cogl-util.h"
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#include "cogl-path-private.h"
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#include "cogl-matrix-private.h"
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#include "cogl-primitives-private.h"
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#ifndef GL_CLIP_PLANE0
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#define GL_CLIP_PLANE0 0x3000
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#define GL_CLIP_PLANE1 0x3001
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#define GL_CLIP_PLANE2 0x3002
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#define GL_CLIP_PLANE3 0x3003
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#define GL_CLIP_PLANE4 0x3004
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#define GL_CLIP_PLANE5 0x3005
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#endif
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static void
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project_vertex (const CoglMatrix *modelview_projection,
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float *vertex)
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{
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int i;
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cogl_matrix_transform_point (modelview_projection,
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&vertex[0], &vertex[1],
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&vertex[2], &vertex[3]);
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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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GLfloat planef[4];
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double planed[4];
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GLfloat angle;
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CoglFramebuffer *framebuffer = cogl_get_draw_framebuffer ();
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CoglMatrixStack *modelview_stack =
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_cogl_framebuffer_get_modelview_stack (framebuffer);
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CoglMatrixStack *projection_stack =
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_cogl_framebuffer_get_projection_stack (framebuffer);
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CoglMatrix inverse_projection;
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_COGL_GET_CONTEXT (ctx, NO_RETVAL);
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_cogl_matrix_stack_get_inverse (projection_stack, &inverse_projection);
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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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_cogl_matrix_stack_push (modelview_stack);
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/* Load the inverse of the projection matrix so we can specify the plane
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* in screen coordinates */
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_cogl_matrix_stack_set (modelview_stack, &inverse_projection);
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/* Rotate about point a */
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_cogl_matrix_stack_translate (modelview_stack,
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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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_cogl_matrix_stack_rotate (modelview_stack, angle, 0.0f, 0.0f, 1.0f);
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_cogl_matrix_stack_translate (modelview_stack,
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-vertex_a[0], -vertex_a[1], -vertex_a[2]);
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_cogl_matrix_stack_flush_to_gl (modelview_stack, COGL_MATRIX_MODELVIEW);
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planef[0] = 0;
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planef[1] = -1.0;
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planef[2] = 0;
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planef[3] = vertex_a[1];
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switch (ctx->driver)
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{
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default:
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g_assert_not_reached ();
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break;
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case COGL_DRIVER_GLES1:
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GE( ctx, glClipPlanef (plane_num, planef) );
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break;
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case COGL_DRIVER_GL:
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planed[0] = planef[0];
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planed[1] = planef[1];
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planed[2] = planef[2];
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planed[3] = planef[3];
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GE( ctx, glClipPlane (plane_num, planed) );
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break;
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}
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_cogl_matrix_stack_pop (modelview_stack);
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}
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static void
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set_clip_planes (float x_1,
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float y_1,
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float x_2,
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float y_2)
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{
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CoglFramebuffer *framebuffer = cogl_get_draw_framebuffer ();
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CoglMatrixStack *modelview_stack =
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_cogl_framebuffer_get_modelview_stack (framebuffer);
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CoglMatrix modelview_matrix;
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CoglMatrixStack *projection_stack =
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_cogl_framebuffer_get_projection_stack (framebuffer);
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CoglMatrix projection_matrix;
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CoglMatrix modelview_projection;
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float signed_area;
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float vertex_tl[4] = { x_1, y_1, 0, 1.0 };
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float vertex_tr[4] = { x_2, y_1, 0, 1.0 };
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float vertex_bl[4] = { x_1, y_2, 0, 1.0 };
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float vertex_br[4] = { x_2, y_2, 0, 1.0 };
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_cogl_matrix_stack_get (projection_stack, &projection_matrix);
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_cogl_matrix_stack_get (modelview_stack, &modelview_matrix);
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cogl_matrix_multiply (&modelview_projection,
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&projection_matrix,
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&modelview_matrix);
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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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/* Calculate the signed area of the polygon formed by the four
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vertices so that we can know its orientation */
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signed_area = (vertex_tl[0] * (vertex_tr[1] - vertex_bl[1])
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+ vertex_tr[0] * (vertex_br[1] - vertex_tl[1])
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+ vertex_br[0] * (vertex_bl[1] - vertex_tr[1])
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+ vertex_bl[0] * (vertex_tl[1] - vertex_br[1]));
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/* Set the clip planes to form lines between all of the vertices
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using the same orientation as we calculated */
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if (signed_area > 0.0f)
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{
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/* counter-clockwise */
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set_clip_plane (GL_CLIP_PLANE0, vertex_tl, vertex_bl);
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set_clip_plane (GL_CLIP_PLANE1, vertex_bl, vertex_br);
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set_clip_plane (GL_CLIP_PLANE2, vertex_br, vertex_tr);
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set_clip_plane (GL_CLIP_PLANE3, vertex_tr, vertex_tl);
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}
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else
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{
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/* clockwise */
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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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static void
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add_stencil_clip_rectangle (float x_1,
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float y_1,
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float x_2,
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float y_2,
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gboolean first)
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{
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CoglFramebuffer *framebuffer = cogl_get_draw_framebuffer ();
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CoglMatrixStack *modelview_stack =
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_cogl_framebuffer_get_modelview_stack (framebuffer);
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CoglMatrixStack *projection_stack =
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_cogl_framebuffer_get_projection_stack (framebuffer);
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_COGL_GET_CONTEXT (ctx, NO_RETVAL);
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/* temporarily swap in our special stenciling pipeline */
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cogl_push_source (ctx->stencil_pipeline);
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/* This can be called from the journal code which doesn't flush
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the matrix stacks between calls so we need to ensure they're
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flushed now */
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_cogl_matrix_stack_flush_to_gl (modelview_stack,
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COGL_MATRIX_MODELVIEW);
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_cogl_matrix_stack_flush_to_gl (projection_stack,
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COGL_MATRIX_PROJECTION);
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if (first)
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{
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GE( ctx, glEnable (GL_STENCIL_TEST) );
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/* Initially disallow everything */
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GE( ctx, glClearStencil (0) );
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GE( ctx, glClear (GL_STENCIL_BUFFER_BIT) );
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/* Punch out a hole to allow the rectangle */
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GE( ctx, glStencilFunc (GL_NEVER, 0x1, 0x1) );
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GE( ctx, glStencilOp (GL_REPLACE, GL_REPLACE, GL_REPLACE) );
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_cogl_rectangle_immediate (x_1, y_1, x_2, y_2);
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}
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else
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{
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/* Add one to every pixel of the stencil buffer in the
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rectangle */
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GE( ctx, glStencilFunc (GL_NEVER, 0x1, 0x3) );
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GE( ctx, glStencilOp (GL_INCR, GL_INCR, GL_INCR) );
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_cogl_rectangle_immediate (x_1, y_1, x_2, y_2);
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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( ctx, glStencilOp (GL_DECR, GL_DECR, GL_DECR) );
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_cogl_matrix_stack_push (projection_stack);
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_cogl_matrix_stack_load_identity (projection_stack);
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_cogl_matrix_stack_push (modelview_stack);
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_cogl_matrix_stack_load_identity (modelview_stack);
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_cogl_matrix_stack_flush_to_gl (modelview_stack,
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COGL_MATRIX_MODELVIEW);
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_cogl_matrix_stack_flush_to_gl (projection_stack,
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COGL_MATRIX_PROJECTION);
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_cogl_rectangle_immediate (-1.0, -1.0, 1.0, 1.0);
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_cogl_matrix_stack_pop (modelview_stack);
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_cogl_matrix_stack_pop (projection_stack);
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}
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/* Restore the stencil mode */
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GE( ctx, glStencilFunc (GL_EQUAL, 0x1, 0x1) );
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GE( ctx, glStencilOp (GL_KEEP, GL_KEEP, GL_KEEP) );
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/* restore the original source pipeline */
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cogl_pop_source ();
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}
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static void
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disable_stencil_buffer (void)
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{
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_COGL_GET_CONTEXT (ctx, NO_RETVAL);
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GE( ctx, glDisable (GL_STENCIL_TEST) );
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}
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static void
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enable_clip_planes (void)
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{
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_COGL_GET_CONTEXT (ctx, NO_RETVAL);
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GE( ctx, glEnable (GL_CLIP_PLANE0) );
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GE( ctx, glEnable (GL_CLIP_PLANE1) );
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GE( ctx, glEnable (GL_CLIP_PLANE2) );
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GE( ctx, glEnable (GL_CLIP_PLANE3) );
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}
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static void
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disable_clip_planes (void)
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{
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_COGL_GET_CONTEXT (ctx, NO_RETVAL);
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GE( ctx, glDisable (GL_CLIP_PLANE3) );
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GE( ctx, glDisable (GL_CLIP_PLANE2) );
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GE( ctx, glDisable (GL_CLIP_PLANE1) );
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GE( ctx, glDisable (GL_CLIP_PLANE0) );
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}
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static gpointer
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_cogl_clip_stack_push_entry (CoglClipStack *clip_stack,
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size_t size,
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CoglClipStackType type)
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{
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CoglClipStack *entry = g_slice_alloc (size);
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/* The new entry starts with a ref count of 1 because the stack
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holds a reference to it as it is the top entry */
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entry->ref_count = 1;
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entry->type = type;
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entry->parent = clip_stack;
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/* We don't need to take a reference to the parent from the entry
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because the we are stealing the ref in the new stack top */
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return entry;
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}
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/* Sets the window-space bounds of the entry based on the projected
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coordinates of the given rectangle */
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static void
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_cogl_clip_stack_entry_set_bounds (CoglClipStack *entry,
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float x_1,
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float y_1,
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float x_2,
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float y_2,
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const CoglMatrix *modelview)
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{
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CoglMatrix projection;
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float viewport[4];
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float verts[4 * 2] = { x_1, y_1, x_2, y_1, x_2, y_2, x_1, y_2 };
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float min_x = G_MAXFLOAT, min_y = G_MAXFLOAT;
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float max_x = -G_MAXFLOAT, max_y = -G_MAXFLOAT;
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int i;
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cogl_get_projection_matrix (&projection);
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cogl_get_viewport (viewport);
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for (i = 0; i < 4; i++)
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{
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float *v = verts + i * 2;
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/* Project the coordinates to window space coordinates */
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_cogl_transform_point (modelview, &projection, viewport, v, v + 1);
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if (v[0] > max_x)
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max_x = v[0];
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if (v[0] < min_x)
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min_x = v[0];
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if (v[1] > max_y)
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max_y = v[1];
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if (v[1] < min_y)
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min_y = v[1];
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}
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entry->bounds_x0 = floorf (min_x);
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entry->bounds_x1 = ceilf (max_x);
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entry->bounds_y0 = floorf (min_y);
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entry->bounds_y1 = ceilf (max_y);
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}
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CoglClipStack *
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_cogl_clip_stack_push_window_rectangle (CoglClipStack *stack,
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int x_offset,
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int y_offset,
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int width,
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int height)
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{
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CoglClipStack *entry;
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entry = _cogl_clip_stack_push_entry (stack,
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sizeof (CoglClipStackWindowRect),
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COGL_CLIP_STACK_WINDOW_RECT);
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entry->bounds_x0 = x_offset;
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entry->bounds_x1 = x_offset + width;
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entry->bounds_y0 = y_offset;
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entry->bounds_y1 = y_offset + height;
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return entry;
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}
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CoglClipStack *
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_cogl_clip_stack_push_rectangle (CoglClipStack *stack,
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float x_1,
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float y_1,
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float x_2,
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float y_2,
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const CoglMatrix *modelview_matrix)
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{
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CoglClipStackRect *entry;
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CoglMatrix matrix_p;
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float v[4];
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/* Make a new entry */
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entry = _cogl_clip_stack_push_entry (stack,
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sizeof (CoglClipStackRect),
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COGL_CLIP_STACK_RECT);
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entry->x0 = x_1;
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entry->y0 = y_1;
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entry->x1 = x_2;
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entry->y1 = y_2;
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entry->matrix = *modelview_matrix;
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/* If the modelview meets these constraints then a transformed rectangle
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* should still be a rectangle when it reaches screen coordinates.
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*
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* FIXME: we are are making certain assumptions about the projection
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* matrix a.t.m and should really be looking at the combined modelview
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* and projection matrix.
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* FIXME: we don't consider rotations that are a multiple of 90 degrees
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* which could be quite common.
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*/
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if (modelview_matrix->xy != 0 || modelview_matrix->xz != 0 ||
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modelview_matrix->yx != 0 || modelview_matrix->yz != 0 ||
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modelview_matrix->zx != 0 || modelview_matrix->zy != 0)
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{
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entry->can_be_scissor = FALSE;
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_cogl_clip_stack_entry_set_bounds ((CoglClipStack *) entry,
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x_1, y_1, x_2, y_2, modelview_matrix);
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}
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else
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{
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CoglClipStack *base_entry = (CoglClipStack *) entry;
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cogl_get_projection_matrix (&matrix_p);
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cogl_get_viewport (v);
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_cogl_transform_point (modelview_matrix, &matrix_p, v, &x_1, &y_1);
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_cogl_transform_point (modelview_matrix, &matrix_p, v, &x_2, &y_2);
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/* Consider that the modelview matrix may flip the rectangle
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* along the x or y axis... */
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#define SWAP(A,B) do { float tmp = B; B = A; A = tmp; } while (0)
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if (x_1 > x_2)
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SWAP (x_1, x_2);
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if (y_1 > y_2)
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SWAP (y_1, y_2);
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#undef SWAP
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base_entry->bounds_x0 = COGL_UTIL_NEARBYINT (x_1);
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base_entry->bounds_y0 = COGL_UTIL_NEARBYINT (y_1);
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base_entry->bounds_x1 = COGL_UTIL_NEARBYINT (x_2);
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base_entry->bounds_y1 = COGL_UTIL_NEARBYINT (y_2);
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entry->can_be_scissor = TRUE;
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}
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return (CoglClipStack *) entry;
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}
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CoglClipStack *
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_cogl_clip_stack_push_from_path (CoglClipStack *stack,
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CoglPath *path,
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const CoglMatrix *modelview_matrix)
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{
|
|
float x_1, y_1, x_2, y_2;
|
|
|
|
_cogl_path_get_bounds (path, &x_1, &y_1, &x_2, &y_2);
|
|
|
|
/* If the path is a simple rectangle then we can divert to pushing a
|
|
rectangle clip instead which usually won't involve the stencil
|
|
buffer */
|
|
if (_cogl_path_is_rectangle (path))
|
|
return _cogl_clip_stack_push_rectangle (stack,
|
|
x_1, y_1,
|
|
x_2, y_2,
|
|
modelview_matrix);
|
|
else
|
|
{
|
|
CoglClipStackPath *entry;
|
|
|
|
entry = _cogl_clip_stack_push_entry (stack,
|
|
sizeof (CoglClipStackPath),
|
|
COGL_CLIP_STACK_PATH);
|
|
|
|
entry->path = cogl_path_copy (path);
|
|
|
|
entry->matrix = *modelview_matrix;
|
|
|
|
_cogl_clip_stack_entry_set_bounds ((CoglClipStack *) entry,
|
|
x_1, y_1, x_2, y_2, modelview_matrix);
|
|
|
|
return (CoglClipStack *) entry;
|
|
}
|
|
}
|
|
|
|
CoglClipStack *
|
|
_cogl_clip_stack_ref (CoglClipStack *entry)
|
|
{
|
|
/* A NULL pointer is considered a valid stack so we should accept
|
|
that as an argument */
|
|
if (entry)
|
|
entry->ref_count++;
|
|
|
|
return entry;
|
|
}
|
|
|
|
void
|
|
_cogl_clip_stack_unref (CoglClipStack *entry)
|
|
{
|
|
/* Unref all of the entries until we hit the root of the list or the
|
|
entry still has a remaining reference */
|
|
while (entry && --entry->ref_count <= 0)
|
|
{
|
|
CoglClipStack *parent = entry->parent;
|
|
|
|
switch (entry->type)
|
|
{
|
|
case COGL_CLIP_STACK_RECT:
|
|
g_slice_free1 (sizeof (CoglClipStackRect), entry);
|
|
break;
|
|
|
|
case COGL_CLIP_STACK_WINDOW_RECT:
|
|
g_slice_free1 (sizeof (CoglClipStackWindowRect), entry);
|
|
break;
|
|
|
|
case COGL_CLIP_STACK_PATH:
|
|
cogl_object_unref (((CoglClipStackPath *) entry)->path);
|
|
g_slice_free1 (sizeof (CoglClipStackPath), entry);
|
|
break;
|
|
|
|
default:
|
|
g_assert_not_reached ();
|
|
}
|
|
|
|
entry = parent;
|
|
}
|
|
}
|
|
|
|
CoglClipStack *
|
|
_cogl_clip_stack_pop (CoglClipStack *stack)
|
|
{
|
|
CoglClipStack *new_top;
|
|
|
|
g_return_val_if_fail (stack != NULL, NULL);
|
|
|
|
/* To pop we are moving the top of the stack to the old top's parent
|
|
node. The stack always needs to have a reference to the top entry
|
|
so we must take a reference to the new top. The stack would have
|
|
previously had a reference to the old top so we need to decrease
|
|
the ref count on that. We need to ref the new head first in case
|
|
this stack was the only thing referencing the old top. In that
|
|
case the call to _cogl_clip_stack_entry_unref will unref the
|
|
parent. */
|
|
new_top = stack->parent;
|
|
|
|
_cogl_clip_stack_ref (new_top);
|
|
|
|
_cogl_clip_stack_unref (stack);
|
|
|
|
return new_top;
|
|
}
|
|
|
|
void
|
|
_cogl_clip_stack_get_bounds (CoglClipStack *stack,
|
|
int *scissor_x0,
|
|
int *scissor_y0,
|
|
int *scissor_x1,
|
|
int *scissor_y1)
|
|
{
|
|
CoglClipStack *entry;
|
|
|
|
*scissor_x0 = 0;
|
|
*scissor_y0 = 0;
|
|
*scissor_x1 = G_MAXINT;
|
|
*scissor_y1 = G_MAXINT;
|
|
|
|
for (entry = stack; entry; entry = entry->parent)
|
|
{
|
|
/* Get the intersection of the current scissor and the bounding
|
|
box of this clip */
|
|
*scissor_x0 = MAX (*scissor_x0, entry->bounds_x0);
|
|
*scissor_y0 = MAX (*scissor_y0, entry->bounds_y0);
|
|
*scissor_x1 = MIN (*scissor_x1, entry->bounds_x1);
|
|
*scissor_y1 = MIN (*scissor_y1, entry->bounds_y1);
|
|
}
|
|
}
|
|
|
|
void
|
|
_cogl_clip_stack_flush (CoglClipStack *stack)
|
|
{
|
|
int has_clip_planes;
|
|
gboolean using_clip_planes = FALSE;
|
|
gboolean using_stencil_buffer = FALSE;
|
|
int scissor_x0;
|
|
int scissor_y0;
|
|
int scissor_x1;
|
|
int scissor_y1;
|
|
CoglMatrixStack *modelview_stack;
|
|
CoglClipStack *entry;
|
|
int scissor_y_start;
|
|
|
|
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
|
|
|
|
/* If we have already flushed this state then we don't need to do
|
|
anything */
|
|
if (ctx->current_clip_stack_valid)
|
|
{
|
|
if (ctx->current_clip_stack == stack)
|
|
return;
|
|
|
|
_cogl_clip_stack_unref (ctx->current_clip_stack);
|
|
}
|
|
|
|
ctx->current_clip_stack_valid = TRUE;
|
|
ctx->current_clip_stack = _cogl_clip_stack_ref (stack);
|
|
|
|
modelview_stack =
|
|
_cogl_framebuffer_get_modelview_stack (cogl_get_draw_framebuffer ());
|
|
|
|
has_clip_planes = cogl_features_available (COGL_FEATURE_FOUR_CLIP_PLANES);
|
|
|
|
if (has_clip_planes)
|
|
disable_clip_planes ();
|
|
disable_stencil_buffer ();
|
|
|
|
/* If the stack is empty then there's nothing else to do */
|
|
if (stack == NULL)
|
|
{
|
|
COGL_NOTE (CLIPPING, "Flushed empty clip stack");
|
|
|
|
ctx->current_clip_stack_uses_stencil = FALSE;
|
|
GE (ctx, glDisable (GL_SCISSOR_TEST));
|
|
return;
|
|
}
|
|
|
|
/* Calculate the scissor rect first so that if we eventually have to
|
|
clear the stencil buffer then the clear will be clipped to the
|
|
intersection of all of the bounding boxes. This saves having to
|
|
clear the whole stencil buffer */
|
|
_cogl_clip_stack_get_bounds (stack,
|
|
&scissor_x0, &scissor_y0,
|
|
&scissor_x1, &scissor_y1);
|
|
|
|
/* Enable scissoring as soon as possible */
|
|
if (scissor_x0 >= scissor_x1 || scissor_y0 >= scissor_y1)
|
|
scissor_x0 = scissor_y0 = scissor_x1 = scissor_y1 = scissor_y_start = 0;
|
|
else
|
|
{
|
|
CoglFramebuffer *framebuffer = cogl_get_draw_framebuffer ();
|
|
|
|
/* We store the entry coordinates in Cogl coordinate space
|
|
* but OpenGL requires the window origin to be the bottom
|
|
* left so we may need to convert the incoming coordinates.
|
|
*
|
|
* NB: Cogl forces all offscreen rendering to be done upside
|
|
* down so in this case no conversion is needed.
|
|
*/
|
|
|
|
if (cogl_is_offscreen (framebuffer))
|
|
scissor_y_start = scissor_y0;
|
|
else
|
|
{
|
|
int framebuffer_height =
|
|
cogl_framebuffer_get_height (framebuffer);
|
|
|
|
scissor_y_start = framebuffer_height - scissor_y1;
|
|
}
|
|
}
|
|
|
|
COGL_NOTE (CLIPPING, "Flushing scissor to (%i, %i, %i, %i)",
|
|
scissor_x0, scissor_y0,
|
|
scissor_x1, scissor_y1);
|
|
|
|
GE (ctx, glEnable (GL_SCISSOR_TEST));
|
|
GE (ctx, glScissor (scissor_x0, scissor_y_start,
|
|
scissor_x1 - scissor_x0,
|
|
scissor_y1 - scissor_y0));
|
|
|
|
/* Add all of the entries. This will end up adding them in the
|
|
reverse order that they were specified but as all of the clips
|
|
are intersecting it should work out the same regardless of the
|
|
order */
|
|
for (entry = stack; entry; entry = entry->parent)
|
|
{
|
|
if (entry->type == COGL_CLIP_STACK_PATH)
|
|
{
|
|
CoglClipStackPath *path_entry = (CoglClipStackPath *) entry;
|
|
|
|
COGL_NOTE (CLIPPING, "Adding stencil clip for path");
|
|
|
|
_cogl_matrix_stack_push (modelview_stack);
|
|
_cogl_matrix_stack_set (modelview_stack, &path_entry->matrix);
|
|
|
|
_cogl_add_path_to_stencil_buffer (path_entry->path,
|
|
using_stencil_buffer,
|
|
TRUE);
|
|
|
|
_cogl_matrix_stack_pop (modelview_stack);
|
|
|
|
using_stencil_buffer = TRUE;
|
|
}
|
|
else if (entry->type == COGL_CLIP_STACK_RECT)
|
|
{
|
|
CoglClipStackRect *rect = (CoglClipStackRect *) entry;
|
|
|
|
/* We don't need to do anything extra if the clip for this
|
|
rectangle was entirely described by its scissor bounds */
|
|
if (!rect->can_be_scissor)
|
|
{
|
|
_cogl_matrix_stack_push (modelview_stack);
|
|
_cogl_matrix_stack_set (modelview_stack, &rect->matrix);
|
|
|
|
/* If we support clip planes and we haven't already used
|
|
them then use that instead */
|
|
if (has_clip_planes)
|
|
{
|
|
COGL_NOTE (CLIPPING, "Adding clip planes clip for rectangle");
|
|
|
|
set_clip_planes (rect->x0,
|
|
rect->y0,
|
|
rect->x1,
|
|
rect->y1);
|
|
using_clip_planes = TRUE;
|
|
/* We can't use clip planes a second time */
|
|
has_clip_planes = FALSE;
|
|
}
|
|
else
|
|
{
|
|
COGL_NOTE (CLIPPING, "Adding stencil clip for rectangle");
|
|
|
|
add_stencil_clip_rectangle (rect->x0,
|
|
rect->y0,
|
|
rect->x1,
|
|
rect->y1,
|
|
!using_stencil_buffer);
|
|
using_stencil_buffer = TRUE;
|
|
}
|
|
|
|
_cogl_matrix_stack_pop (modelview_stack);
|
|
}
|
|
}
|
|
/* We don't need to do anything for window space rectangles
|
|
because their functionality is entirely implemented by the
|
|
entry bounding box */
|
|
}
|
|
|
|
/* Enabling clip planes is delayed to now so that they won't affect
|
|
setting up the stencil buffer */
|
|
if (using_clip_planes)
|
|
enable_clip_planes ();
|
|
|
|
ctx->current_clip_stack_uses_stencil = using_stencil_buffer;
|
|
}
|
|
|
|
void
|
|
_cogl_clip_stack_dirty (void)
|
|
{
|
|
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
|
|
|
|
if (ctx->current_clip_stack_valid)
|
|
{
|
|
ctx->current_clip_stack_valid = FALSE;
|
|
_cogl_clip_stack_unref (ctx->current_clip_stack);
|
|
}
|
|
}
|