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mutter-performance-source/clutter/cogl/common/cogl-clip-stack.c
Robert Bragg e82f656590 [Automatic fixed-to-float.sh change] Applies all scripted changes
This is the result of running a number of sed and perl scripts over the code to
do 90% of the work in converting from 16.16 fixed to single precision floating
point.

Note: A pristine cogl-fixed.c has been maintained as a standalone utility API
      so that applications may still take advantage of fixed point if they
      desire for certain optimisations where lower precision may be acceptable.

Note: no API changes were made in Clutter, only in Cogl.

Overview of changes:
- Within clutter/* all usage of the COGL_FIXED_ macros have been changed to use
the CLUTTER_FIXED_ macros.

- Within cogl/* all usage of the COGL_FIXED_ macros have been completly stripped
and expanded into code that works with single precision floats instead.

- Uses of cogl_fixed_* have been replaced with single precision math.h
alternatives.

- Uses of COGL_ANGLE_* and cogl_angle_* have been replaced so we use a float for
angles and math.h replacements.
2009-01-20 16:20:54 +00:00

352 lines
8.9 KiB
C

/*
* Clutter COGL
*
* A basic GL/GLES Abstraction/Utility Layer
*
* Authored By Matthew Allum <mallum@openedhand.com>
*
* Copyright (C) 2008 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 <string.h>
#include "cogl.h"
#include "cogl-clip-stack.h"
#include "cogl-primitives.h"
#include "cogl-context.h"
/* These are defined in the particular backend (float in GL vs fixed
in GL ES) */
void _cogl_set_clip_planes (float x,
float y,
float width,
float height);
void _cogl_add_stencil_clip (float x,
float y,
float width,
float height,
gboolean first);
void _cogl_add_path_to_stencil_buffer (floatVec2 nodes_min,
floatVec2 nodes_max,
guint path_size,
CoglPathNode *path,
gboolean merge);
void _cogl_enable_clip_planes (void);
void _cogl_disable_clip_planes (void);
void _cogl_disable_stencil_buffer (void);
void _cogl_set_matrix (const float *matrix);
typedef struct _CoglClipStack CoglClipStack;
typedef struct _CoglClipStackEntryRect CoglClipStackEntryRect;
typedef struct _CoglClipStackEntryPath CoglClipStackEntryPath;
typedef enum
{
COGL_CLIP_STACK_RECT,
COGL_CLIP_STACK_PATH
} CoglClipStackEntryType;
struct _CoglClipStack
{
GList *stack_top;
};
struct _CoglClipStackEntryRect
{
CoglClipStackEntryType type;
/* The rectangle for this clip */
float x_offset;
float y_offset;
float width;
float height;
/* The matrix that was current when the clip was set */
float matrix[16];
};
struct _CoglClipStackEntryPath
{
CoglClipStackEntryType type;
/* The matrix that was current when the clip was set */
float matrix[16];
floatVec2 path_nodes_min;
floatVec2 path_nodes_max;
guint path_size;
CoglPathNode path[1];
};
void
cogl_clip_set (float x_offset,
float y_offset,
float width,
float height)
{
CoglClipStackEntryRect *entry;
CoglClipStack *stack;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
stack = (CoglClipStack *) ctx->clip.stacks->data;
entry = g_slice_new (CoglClipStackEntryRect);
/* Make a new entry */
entry->type = COGL_CLIP_STACK_RECT;
entry->x_offset = x_offset;
entry->y_offset = y_offset;
entry->width = width;
entry->height = height;
cogl_get_modelview_matrix (entry->matrix);
/* Store it in the stack */
stack->stack_top = g_list_prepend (stack->stack_top, entry);
ctx->clip.stack_dirty = TRUE;
}
void
cogl_clip_set_from_path_preserve (void)
{
CoglClipStackEntryPath *entry;
CoglClipStack *stack;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
stack = (CoglClipStack *) ctx->clip.stacks->data;
entry = g_malloc (sizeof (CoglClipStackEntryPath)
+ sizeof (CoglPathNode) * (ctx->path_nodes->len - 1));
entry->type = COGL_CLIP_STACK_PATH;
entry->path_nodes_min = ctx->path_nodes_min;
entry->path_nodes_max = ctx->path_nodes_max;
entry->path_size = ctx->path_nodes->len;
memcpy (entry->path, ctx->path_nodes->data,
sizeof (CoglPathNode) * ctx->path_nodes->len);
cogl_get_modelview_matrix (entry->matrix);
/* Store it in the stack */
stack->stack_top = g_list_prepend (stack->stack_top, entry);
ctx->clip.stack_dirty = TRUE;
}
void
cogl_clip_set_from_path (void)
{
cogl_clip_set_from_path_preserve ();
cogl_path_new ();
}
void
cogl_clip_unset (void)
{
gpointer entry;
CoglClipStack *stack;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
stack = (CoglClipStack *) ctx->clip.stacks->data;
g_return_if_fail (stack->stack_top != NULL);
entry = stack->stack_top->data;
/* Remove the top entry from the stack */
if (*(CoglClipStackEntryType *) entry == COGL_CLIP_STACK_RECT)
g_slice_free (CoglClipStackEntryRect, entry);
else
g_free (entry);
stack->stack_top = g_list_delete_link (stack->stack_top,
stack->stack_top);
ctx->clip.stack_dirty = TRUE;
}
void
_cogl_clip_stack_rebuild (void)
{
int has_clip_planes = cogl_features_available (COGL_FEATURE_FOUR_CLIP_PLANES);
gboolean using_clip_planes = FALSE;
gboolean using_stencil_buffer = FALSE;
GList *node;
CoglClipStack *stack;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
stack = (CoglClipStack *) ctx->clip.stacks->data;
ctx->clip.stack_dirty = FALSE;
ctx->clip.stencil_used = FALSE;
_cogl_disable_clip_planes ();
_cogl_disable_stencil_buffer ();
/* If the stack is empty then there's nothing else to do */
if (stack->stack_top == NULL)
return;
/* Find the bottom of the stack */
for (node = stack->stack_top; node->next; node = node->next);
/* Re-add every entry from the bottom of the stack up */
for (; node; node = node->prev)
{
gpointer entry = node->data;
if (*(CoglClipStackEntryType *) entry == COGL_CLIP_STACK_PATH)
{
CoglClipStackEntryPath *path = (CoglClipStackEntryPath *) entry;
cogl_push_matrix ();
_cogl_set_matrix (path->matrix);
_cogl_add_path_to_stencil_buffer (path->path_nodes_min,
path->path_nodes_max,
path->path_size,
path->path,
using_stencil_buffer);
cogl_pop_matrix ();
using_stencil_buffer = TRUE;
/* We can't use clip planes any more */
has_clip_planes = FALSE;
}
else
{
CoglClipStackEntryRect *rect = (CoglClipStackEntryRect *) entry;
cogl_push_matrix ();
_cogl_set_matrix (rect->matrix);
/* If this is the first entry and we support clip planes then use
that instead */
if (has_clip_planes)
{
_cogl_set_clip_planes (rect->x_offset,
rect->y_offset,
rect->width,
rect->height);
using_clip_planes = TRUE;
/* We can't use clip planes a second time */
has_clip_planes = FALSE;
}
else
{
_cogl_add_stencil_clip (rect->x_offset,
rect->y_offset,
rect->width,
rect->height,
!using_stencil_buffer);
using_stencil_buffer = TRUE;
}
cogl_pop_matrix ();
}
}
/* Enabling clip planes is delayed to now so that they won't affect
setting up the stencil buffer */
if (using_clip_planes)
_cogl_enable_clip_planes ();
ctx->clip.stencil_used = using_stencil_buffer;
}
void
cogl_clip_ensure (void)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (ctx->clip.stack_dirty)
_cogl_clip_stack_rebuild ();
}
void
cogl_clip_stack_save (void)
{
CoglClipStack *stack;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
stack = g_slice_new (CoglClipStack);
stack->stack_top = NULL;
ctx->clip.stacks = g_slist_prepend (ctx->clip.stacks, stack);
ctx->clip.stack_dirty = TRUE;
}
void
cogl_clip_stack_restore (void)
{
CoglClipStack *stack;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
g_return_if_fail (ctx->clip.stacks != NULL);
stack = (CoglClipStack *) ctx->clip.stacks->data;
/* Empty the current stack */
while (stack->stack_top)
cogl_clip_unset ();
/* Revert to an old stack */
g_slice_free (CoglClipStack, stack);
ctx->clip.stacks = g_slist_delete_link (ctx->clip.stacks,
ctx->clip.stacks);
ctx->clip.stack_dirty = TRUE;
}
void
_cogl_clip_stack_state_init (void)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
ctx->clip.stacks = NULL;
ctx->clip.stack_dirty = TRUE;
/* Add an intial stack */
cogl_clip_stack_save ();
}
void
_cogl_clip_stack_state_destroy (void)
{
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
/* Destroy all of the stacks */
while (ctx->clip.stacks)
cogl_clip_stack_restore ();
}