mirror of
https://github.com/brl/mutter.git
synced 2024-11-29 19:40:43 -05:00
f7b1bab1ad
Some of the functions we were calling in cogl_framebuffer_clear[4f] were referring to the current framebuffer, which would result in a crash if nothing had been pushed before trying to explicitly clear a given framebuffer. Reviewed-by: Neil Roberts <neil@linux.intel.com>
765 lines
24 KiB
C
765 lines
24 KiB
C
/*
|
|
* Cogl
|
|
*
|
|
* An object oriented GL/GLES Abstraction/Utility Layer
|
|
*
|
|
* Copyright (C) 2007,2008,2009,2010 Intel Corporation.
|
|
*
|
|
* 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, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
*
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include "config.h"
|
|
#endif
|
|
|
|
#include <string.h>
|
|
#include <math.h>
|
|
|
|
#include <glib.h>
|
|
|
|
#include "cogl.h"
|
|
#include "cogl-clip-stack.h"
|
|
#include "cogl-primitives.h"
|
|
#include "cogl-context-private.h"
|
|
#include "cogl-internal.h"
|
|
#include "cogl-framebuffer-private.h"
|
|
#include "cogl-journal-private.h"
|
|
#include "cogl-util.h"
|
|
#include "cogl-path-private.h"
|
|
#include "cogl-matrix-private.h"
|
|
#include "cogl-primitives-private.h"
|
|
|
|
#ifndef GL_CLIP_PLANE0
|
|
#define GL_CLIP_PLANE0 0x3000
|
|
#define GL_CLIP_PLANE1 0x3001
|
|
#define GL_CLIP_PLANE2 0x3002
|
|
#define GL_CLIP_PLANE3 0x3003
|
|
#define GL_CLIP_PLANE4 0x3004
|
|
#define GL_CLIP_PLANE5 0x3005
|
|
#endif
|
|
|
|
static void
|
|
project_vertex (const CoglMatrix *modelview_projection,
|
|
float *vertex)
|
|
{
|
|
int i;
|
|
|
|
cogl_matrix_transform_point (modelview_projection,
|
|
&vertex[0], &vertex[1],
|
|
&vertex[2], &vertex[3]);
|
|
|
|
/* Convert from homogenized coordinates */
|
|
for (i = 0; i < 4; i++)
|
|
vertex[i] /= vertex[3];
|
|
}
|
|
|
|
static void
|
|
set_clip_plane (CoglFramebuffer *framebuffer,
|
|
GLint plane_num,
|
|
const float *vertex_a,
|
|
const float *vertex_b)
|
|
{
|
|
GLfloat planef[4];
|
|
double planed[4];
|
|
GLfloat angle;
|
|
CoglMatrixStack *modelview_stack =
|
|
_cogl_framebuffer_get_modelview_stack (framebuffer);
|
|
CoglMatrixStack *projection_stack =
|
|
_cogl_framebuffer_get_projection_stack (framebuffer);
|
|
CoglMatrix inverse_projection;
|
|
|
|
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
|
|
|
|
_cogl_matrix_stack_get_inverse (projection_stack, &inverse_projection);
|
|
|
|
/* Calculate the angle between the axes and the line crossing the
|
|
two points */
|
|
angle = atan2f (vertex_b[1] - vertex_a[1],
|
|
vertex_b[0] - vertex_a[0]) * (180.0/G_PI);
|
|
|
|
_cogl_matrix_stack_push (modelview_stack);
|
|
|
|
/* Load the inverse of the projection matrix so we can specify the plane
|
|
* in screen coordinates */
|
|
_cogl_matrix_stack_set (modelview_stack, &inverse_projection);
|
|
|
|
/* Rotate about point a */
|
|
_cogl_matrix_stack_translate (modelview_stack,
|
|
vertex_a[0], vertex_a[1], vertex_a[2]);
|
|
/* Rotate the plane by the calculated angle so that it will connect
|
|
the two points */
|
|
_cogl_matrix_stack_rotate (modelview_stack, angle, 0.0f, 0.0f, 1.0f);
|
|
_cogl_matrix_stack_translate (modelview_stack,
|
|
-vertex_a[0], -vertex_a[1], -vertex_a[2]);
|
|
|
|
_cogl_matrix_stack_flush_to_gl (modelview_stack, COGL_MATRIX_MODELVIEW);
|
|
|
|
planef[0] = 0;
|
|
planef[1] = -1.0;
|
|
planef[2] = 0;
|
|
planef[3] = vertex_a[1];
|
|
|
|
switch (ctx->driver)
|
|
{
|
|
default:
|
|
g_assert_not_reached ();
|
|
break;
|
|
|
|
case COGL_DRIVER_GLES1:
|
|
GE( ctx, glClipPlanef (plane_num, planef) );
|
|
break;
|
|
|
|
case COGL_DRIVER_GL:
|
|
planed[0] = planef[0];
|
|
planed[1] = planef[1];
|
|
planed[2] = planef[2];
|
|
planed[3] = planef[3];
|
|
GE( ctx, glClipPlane (plane_num, planed) );
|
|
break;
|
|
}
|
|
|
|
_cogl_matrix_stack_pop (modelview_stack);
|
|
}
|
|
|
|
static void
|
|
set_clip_planes (CoglFramebuffer *framebuffer,
|
|
float x_1,
|
|
float y_1,
|
|
float x_2,
|
|
float y_2)
|
|
{
|
|
CoglMatrixStack *modelview_stack =
|
|
_cogl_framebuffer_get_modelview_stack (framebuffer);
|
|
CoglMatrix modelview_matrix;
|
|
CoglMatrixStack *projection_stack =
|
|
_cogl_framebuffer_get_projection_stack (framebuffer);
|
|
CoglMatrix projection_matrix;
|
|
CoglMatrix modelview_projection;
|
|
float signed_area;
|
|
|
|
float vertex_tl[4] = { x_1, y_1, 0, 1.0 };
|
|
float vertex_tr[4] = { x_2, y_1, 0, 1.0 };
|
|
float vertex_bl[4] = { x_1, y_2, 0, 1.0 };
|
|
float vertex_br[4] = { x_2, y_2, 0, 1.0 };
|
|
|
|
_cogl_matrix_stack_get (projection_stack, &projection_matrix);
|
|
_cogl_matrix_stack_get (modelview_stack, &modelview_matrix);
|
|
|
|
cogl_matrix_multiply (&modelview_projection,
|
|
&projection_matrix,
|
|
&modelview_matrix);
|
|
|
|
project_vertex (&modelview_projection, vertex_tl);
|
|
project_vertex (&modelview_projection, vertex_tr);
|
|
project_vertex (&modelview_projection, vertex_bl);
|
|
project_vertex (&modelview_projection, vertex_br);
|
|
|
|
/* Calculate the signed area of the polygon formed by the four
|
|
vertices so that we can know its orientation */
|
|
signed_area = (vertex_tl[0] * (vertex_tr[1] - vertex_bl[1])
|
|
+ vertex_tr[0] * (vertex_br[1] - vertex_tl[1])
|
|
+ vertex_br[0] * (vertex_bl[1] - vertex_tr[1])
|
|
+ vertex_bl[0] * (vertex_tl[1] - vertex_br[1]));
|
|
|
|
/* Set the clip planes to form lines between all of the vertices
|
|
using the same orientation as we calculated */
|
|
if (signed_area > 0.0f)
|
|
{
|
|
/* counter-clockwise */
|
|
set_clip_plane (framebuffer, GL_CLIP_PLANE0, vertex_tl, vertex_bl);
|
|
set_clip_plane (framebuffer, GL_CLIP_PLANE1, vertex_bl, vertex_br);
|
|
set_clip_plane (framebuffer, GL_CLIP_PLANE2, vertex_br, vertex_tr);
|
|
set_clip_plane (framebuffer, GL_CLIP_PLANE3, vertex_tr, vertex_tl);
|
|
}
|
|
else
|
|
{
|
|
/* clockwise */
|
|
set_clip_plane (framebuffer, GL_CLIP_PLANE0, vertex_tl, vertex_tr);
|
|
set_clip_plane (framebuffer, GL_CLIP_PLANE1, vertex_tr, vertex_br);
|
|
set_clip_plane (framebuffer, GL_CLIP_PLANE2, vertex_br, vertex_bl);
|
|
set_clip_plane (framebuffer, GL_CLIP_PLANE3, vertex_bl, vertex_tl);
|
|
}
|
|
}
|
|
|
|
static void
|
|
add_stencil_clip_rectangle (CoglFramebuffer *framebuffer,
|
|
float x_1,
|
|
float y_1,
|
|
float x_2,
|
|
float y_2,
|
|
gboolean first)
|
|
{
|
|
CoglMatrixStack *modelview_stack =
|
|
_cogl_framebuffer_get_modelview_stack (framebuffer);
|
|
CoglMatrixStack *projection_stack =
|
|
_cogl_framebuffer_get_projection_stack (framebuffer);
|
|
|
|
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
|
|
|
|
/* temporarily swap in our special stenciling pipeline */
|
|
cogl_push_source (ctx->stencil_pipeline);
|
|
|
|
/* This can be called from the journal code which doesn't flush
|
|
the matrix stacks between calls so we need to ensure they're
|
|
flushed now */
|
|
_cogl_matrix_stack_flush_to_gl (modelview_stack,
|
|
COGL_MATRIX_MODELVIEW);
|
|
_cogl_matrix_stack_flush_to_gl (projection_stack,
|
|
COGL_MATRIX_PROJECTION);
|
|
|
|
if (first)
|
|
{
|
|
GE( ctx, glEnable (GL_STENCIL_TEST) );
|
|
|
|
/* Initially disallow everything */
|
|
GE( ctx, glClearStencil (0) );
|
|
GE( ctx, glClear (GL_STENCIL_BUFFER_BIT) );
|
|
|
|
/* Punch out a hole to allow the rectangle */
|
|
GE( ctx, glStencilFunc (GL_NEVER, 0x1, 0x1) );
|
|
GE( ctx, glStencilOp (GL_REPLACE, GL_REPLACE, GL_REPLACE) );
|
|
|
|
_cogl_rectangle_immediate (x_1, y_1, x_2, y_2);
|
|
}
|
|
else
|
|
{
|
|
/* Add one to every pixel of the stencil buffer in the
|
|
rectangle */
|
|
GE( ctx, glStencilFunc (GL_NEVER, 0x1, 0x3) );
|
|
GE( ctx, glStencilOp (GL_INCR, GL_INCR, GL_INCR) );
|
|
_cogl_rectangle_immediate (x_1, y_1, x_2, y_2);
|
|
|
|
/* Subtract one from all pixels in the stencil buffer so that
|
|
only pixels where both the original stencil buffer and the
|
|
rectangle are set will be valid */
|
|
GE( ctx, glStencilOp (GL_DECR, GL_DECR, GL_DECR) );
|
|
|
|
_cogl_matrix_stack_push (projection_stack);
|
|
_cogl_matrix_stack_load_identity (projection_stack);
|
|
|
|
_cogl_matrix_stack_push (modelview_stack);
|
|
_cogl_matrix_stack_load_identity (modelview_stack);
|
|
|
|
_cogl_matrix_stack_flush_to_gl (modelview_stack,
|
|
COGL_MATRIX_MODELVIEW);
|
|
_cogl_matrix_stack_flush_to_gl (projection_stack,
|
|
COGL_MATRIX_PROJECTION);
|
|
|
|
_cogl_rectangle_immediate (-1.0, -1.0, 1.0, 1.0);
|
|
|
|
_cogl_matrix_stack_pop (modelview_stack);
|
|
_cogl_matrix_stack_pop (projection_stack);
|
|
}
|
|
|
|
/* Restore the stencil mode */
|
|
GE( ctx, glStencilFunc (GL_EQUAL, 0x1, 0x1) );
|
|
GE( ctx, glStencilOp (GL_KEEP, GL_KEEP, GL_KEEP) );
|
|
|
|
/* restore the original source pipeline */
|
|
cogl_pop_source ();
|
|
}
|
|
|
|
static void
|
|
disable_stencil_buffer (void)
|
|
{
|
|
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
|
|
|
|
GE( ctx, glDisable (GL_STENCIL_TEST) );
|
|
}
|
|
|
|
static void
|
|
enable_clip_planes (void)
|
|
{
|
|
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
|
|
|
|
GE( ctx, glEnable (GL_CLIP_PLANE0) );
|
|
GE( ctx, glEnable (GL_CLIP_PLANE1) );
|
|
GE( ctx, glEnable (GL_CLIP_PLANE2) );
|
|
GE( ctx, glEnable (GL_CLIP_PLANE3) );
|
|
}
|
|
|
|
static void
|
|
disable_clip_planes (void)
|
|
{
|
|
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
|
|
|
|
GE( ctx, glDisable (GL_CLIP_PLANE3) );
|
|
GE( ctx, glDisable (GL_CLIP_PLANE2) );
|
|
GE( ctx, glDisable (GL_CLIP_PLANE1) );
|
|
GE( ctx, glDisable (GL_CLIP_PLANE0) );
|
|
}
|
|
|
|
static gpointer
|
|
_cogl_clip_stack_push_entry (CoglClipStack *clip_stack,
|
|
size_t size,
|
|
CoglClipStackType type)
|
|
{
|
|
CoglClipStack *entry = g_slice_alloc (size);
|
|
|
|
/* The new entry starts with a ref count of 1 because the stack
|
|
holds a reference to it as it is the top entry */
|
|
entry->ref_count = 1;
|
|
entry->type = type;
|
|
entry->parent = clip_stack;
|
|
|
|
/* We don't need to take a reference to the parent from the entry
|
|
because the we are stealing the ref in the new stack top */
|
|
|
|
return entry;
|
|
}
|
|
|
|
/* Sets the window-space bounds of the entry based on the projected
|
|
coordinates of the given rectangle */
|
|
static void
|
|
_cogl_clip_stack_entry_set_bounds (CoglClipStack *entry,
|
|
float x_1,
|
|
float y_1,
|
|
float x_2,
|
|
float y_2,
|
|
const CoglMatrix *modelview)
|
|
{
|
|
CoglMatrix projection;
|
|
float viewport[4];
|
|
float verts[4 * 2] = { x_1, y_1, x_2, y_1, x_2, y_2, x_1, y_2 };
|
|
float min_x = G_MAXFLOAT, min_y = G_MAXFLOAT;
|
|
float max_x = -G_MAXFLOAT, max_y = -G_MAXFLOAT;
|
|
int i;
|
|
|
|
cogl_get_projection_matrix (&projection);
|
|
cogl_get_viewport (viewport);
|
|
|
|
for (i = 0; i < 4; i++)
|
|
{
|
|
float *v = verts + i * 2;
|
|
|
|
/* Project the coordinates to window space coordinates */
|
|
_cogl_transform_point (modelview, &projection, viewport, v, v + 1);
|
|
|
|
if (v[0] > max_x)
|
|
max_x = v[0];
|
|
if (v[0] < min_x)
|
|
min_x = v[0];
|
|
if (v[1] > max_y)
|
|
max_y = v[1];
|
|
if (v[1] < min_y)
|
|
min_y = v[1];
|
|
}
|
|
|
|
entry->bounds_x0 = floorf (min_x);
|
|
entry->bounds_x1 = ceilf (max_x);
|
|
entry->bounds_y0 = floorf (min_y);
|
|
entry->bounds_y1 = ceilf (max_y);
|
|
}
|
|
|
|
CoglClipStack *
|
|
_cogl_clip_stack_push_window_rectangle (CoglClipStack *stack,
|
|
int x_offset,
|
|
int y_offset,
|
|
int width,
|
|
int height)
|
|
{
|
|
CoglClipStack *entry;
|
|
|
|
entry = _cogl_clip_stack_push_entry (stack,
|
|
sizeof (CoglClipStackWindowRect),
|
|
COGL_CLIP_STACK_WINDOW_RECT);
|
|
|
|
entry->bounds_x0 = x_offset;
|
|
entry->bounds_x1 = x_offset + width;
|
|
entry->bounds_y0 = y_offset;
|
|
entry->bounds_y1 = y_offset + height;
|
|
|
|
return entry;
|
|
}
|
|
|
|
CoglClipStack *
|
|
_cogl_clip_stack_push_rectangle (CoglClipStack *stack,
|
|
float x_1,
|
|
float y_1,
|
|
float x_2,
|
|
float y_2,
|
|
const CoglMatrix *modelview_matrix)
|
|
{
|
|
CoglClipStackRect *entry;
|
|
CoglMatrix matrix_p;
|
|
float v[4];
|
|
|
|
/* Make a new entry */
|
|
entry = _cogl_clip_stack_push_entry (stack,
|
|
sizeof (CoglClipStackRect),
|
|
COGL_CLIP_STACK_RECT);
|
|
|
|
entry->x0 = x_1;
|
|
entry->y0 = y_1;
|
|
entry->x1 = x_2;
|
|
entry->y1 = y_2;
|
|
|
|
entry->matrix = *modelview_matrix;
|
|
|
|
/* If the modelview meets these constraints then a transformed rectangle
|
|
* should still be a rectangle when it reaches screen coordinates.
|
|
*
|
|
* FIXME: we are are making certain assumptions about the projection
|
|
* matrix a.t.m and should really be looking at the combined modelview
|
|
* and projection matrix.
|
|
* FIXME: we don't consider rotations that are a multiple of 90 degrees
|
|
* which could be quite common.
|
|
*/
|
|
if (modelview_matrix->xy != 0 || modelview_matrix->xz != 0 ||
|
|
modelview_matrix->yx != 0 || modelview_matrix->yz != 0 ||
|
|
modelview_matrix->zx != 0 || modelview_matrix->zy != 0)
|
|
{
|
|
entry->can_be_scissor = FALSE;
|
|
_cogl_clip_stack_entry_set_bounds ((CoglClipStack *) entry,
|
|
x_1, y_1, x_2, y_2, modelview_matrix);
|
|
}
|
|
else
|
|
{
|
|
CoglClipStack *base_entry = (CoglClipStack *) entry;
|
|
|
|
cogl_get_projection_matrix (&matrix_p);
|
|
cogl_get_viewport (v);
|
|
|
|
_cogl_transform_point (modelview_matrix, &matrix_p, v, &x_1, &y_1);
|
|
_cogl_transform_point (modelview_matrix, &matrix_p, v, &x_2, &y_2);
|
|
|
|
/* Consider that the modelview matrix may flip the rectangle
|
|
* along the x or y axis... */
|
|
#define SWAP(A,B) do { float tmp = B; B = A; A = tmp; } while (0)
|
|
if (x_1 > x_2)
|
|
SWAP (x_1, x_2);
|
|
if (y_1 > y_2)
|
|
SWAP (y_1, y_2);
|
|
#undef SWAP
|
|
|
|
base_entry->bounds_x0 = COGL_UTIL_NEARBYINT (x_1);
|
|
base_entry->bounds_y0 = COGL_UTIL_NEARBYINT (y_1);
|
|
base_entry->bounds_x1 = COGL_UTIL_NEARBYINT (x_2);
|
|
base_entry->bounds_y1 = COGL_UTIL_NEARBYINT (y_2);
|
|
entry->can_be_scissor = TRUE;
|
|
}
|
|
|
|
return (CoglClipStack *) entry;
|
|
}
|
|
|
|
CoglClipStack *
|
|
_cogl_clip_stack_push_from_path (CoglClipStack *stack,
|
|
CoglPath *path,
|
|
const CoglMatrix *modelview_matrix)
|
|
{
|
|
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,
|
|
CoglFramebuffer *framebuffer)
|
|
{
|
|
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 (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
|
|
{
|
|
/* 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 (framebuffer,
|
|
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 (framebuffer,
|
|
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);
|
|
}
|
|
}
|