mutter/cogl/cogl-debug.c
Robert Bragg e3d6bc36d3 Re-design the matrix stack using a graph of ops
This re-designs the matrix stack so we now keep track of each separate
operation such as rotating, scaling, translating and multiplying as
immutable, ref-counted nodes in a graph.

Being a "graph" here means that different transformations composed of
a sequence of linked operation nodes may share nodes.

The first node in a matrix-stack is always a LOAD_IDENTITY operation.

As an example consider if an application where to draw three rectangles
A, B and C something like this:

cogl_framebuffer_scale (fb, 2, 2, 2);
cogl_framebuffer_push_matrix(fb);

  cogl_framebuffer_translate (fb, 10, 0, 0);

  cogl_framebuffer_push_matrix(fb);

    cogl_framebuffer_rotate (fb, 45, 0, 0, 1);
    cogl_framebuffer_draw_rectangle (...); /* A */

  cogl_framebuffer_pop_matrix(fb);

  cogl_framebuffer_draw_rectangle (...); /* B */

cogl_framebuffer_pop_matrix(fb);

cogl_framebuffer_push_matrix(fb);
  cogl_framebuffer_set_modelview_matrix (fb, &mv);
  cogl_framebuffer_draw_rectangle (...); /* C */
cogl_framebuffer_pop_matrix(fb);

That would result in a graph of nodes like this:

LOAD_IDENTITY
      |
    SCALE
    /     \
SAVE       LOAD
  |           |
TRANSLATE    RECTANGLE(C)
  |     \
SAVE    RECTANGLE(B)
  |
ROTATE
  |
RECTANGLE(A)

Each push adds a SAVE operation which serves as a marker to rewind too
when a corresponding pop is issued and also each SAVE node may also
store a cached matrix representing the composition of all its ancestor
nodes. This means if we repeatedly need to resolve a real CoglMatrix
for a given node then we don't need to repeat the composition.

Some advantages of this design are:
- A single pointer to any node in the graph can now represent a
  complete, immutable transformation that can be logged for example
  into a journal. Previously we were storing a full CoglMatrix in
  each journal entry which is 16 floats for the matrix itself as well
  as space for flags and another 16 floats for possibly storing a
  cache of the inverse. This means that we significantly reduce
  the size of the journal when drawing lots of primitives and we also
  avoid copying over 128 bytes per entry.
- It becomes much cheaper to check for equality. In cases where some
  (unlikely) false negatives are allowed simply comparing the pointers
  of two matrix stack graph entries is enough. Previously we would use
  memcmp() to compare matrices.
- It becomes easier to do comparisons of transformations. By looking
  for the common ancestry between nodes we can determine the operations
  that differentiate the transforms and use those to gain a high level
  understanding of the differences. For example we use this in the
  journal to be able to efficiently determine when two rectangle
  transforms only differ by some translation so that we can perform
  software clipping.

Reviewed-by: Neil Roberts <neil@linux.intel.com>

(cherry picked from commit f75aee93f6b293ca7a7babbd8fcc326ee6bf7aef)
2012-08-06 14:27:40 +01:00

288 lines
9.5 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2009 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 <stdlib.h>
#include <glib/gi18n-lib.h>
#include "cogl-private.h"
#include "cogl-debug.h"
#include "cogl1-context.h"
/* XXX: If you add a debug option, please also add an option
* definition to cogl-debug-options.h. This will enable us - for
* example - to emit a "help" description for the option.
*/
/* NB: Only these options get enabled if COGL_DEBUG=all is
* used since they don't affect the behaviour of Cogl they
* simply print out verbose information */
static const GDebugKey cogl_log_debug_keys[] = {
{ "object", COGL_DEBUG_OBJECT },
{ "slicing", COGL_DEBUG_SLICING },
{ "atlas", COGL_DEBUG_ATLAS },
{ "blend-strings", COGL_DEBUG_BLEND_STRINGS },
{ "journal", COGL_DEBUG_JOURNAL },
{ "batching", COGL_DEBUG_BATCHING },
{ "matrices", COGL_DEBUG_MATRICES },
{ "draw", COGL_DEBUG_DRAW },
{ "opengl", COGL_DEBUG_OPENGL },
{ "pango", COGL_DEBUG_PANGO },
{ "show-source", COGL_DEBUG_SHOW_SOURCE},
{ "offscreen", COGL_DEBUG_OFFSCREEN },
{ "texture-pixmap", COGL_DEBUG_TEXTURE_PIXMAP },
{ "bitmap", COGL_DEBUG_BITMAP },
{ "clipping", COGL_DEBUG_CLIPPING },
{ "winsys", COGL_DEBUG_WINSYS },
{ "performance", COGL_DEBUG_PERFORMANCE }
};
static const int n_cogl_log_debug_keys =
G_N_ELEMENTS (cogl_log_debug_keys);
static const GDebugKey cogl_behavioural_debug_keys[] = {
{ "rectangles", COGL_DEBUG_RECTANGLES },
{ "disable-batching", COGL_DEBUG_DISABLE_BATCHING },
{ "disable-vbos", COGL_DEBUG_DISABLE_VBOS },
{ "disable-pbos", COGL_DEBUG_DISABLE_PBOS },
{ "disable-software-transform", COGL_DEBUG_DISABLE_SOFTWARE_TRANSFORM },
{ "dump-atlas-image", COGL_DEBUG_DUMP_ATLAS_IMAGE },
{ "disable-atlas", COGL_DEBUG_DISABLE_ATLAS },
{ "disable-shared-atlas", COGL_DEBUG_DISABLE_SHARED_ATLAS },
{ "disable-texturing", COGL_DEBUG_DISABLE_TEXTURING},
{ "disable-arbfp", COGL_DEBUG_DISABLE_ARBFP},
{ "disable-fixed", COGL_DEBUG_DISABLE_FIXED},
{ "disable-glsl", COGL_DEBUG_DISABLE_GLSL},
{ "disable-blending", COGL_DEBUG_DISABLE_BLENDING},
{ "disable-npot-textures", COGL_DEBUG_DISABLE_NPOT_TEXTURES},
{ "wireframe", COGL_DEBUG_WIREFRAME},
{ "disable-software-clip", COGL_DEBUG_DISABLE_SOFTWARE_CLIP},
{ "disable-program-caches", COGL_DEBUG_DISABLE_PROGRAM_CACHES},
{ "disable-fast-read-pixel", COGL_DEBUG_DISABLE_FAST_READ_PIXEL}
};
static const int n_cogl_behavioural_debug_keys =
G_N_ELEMENTS (cogl_behavioural_debug_keys);
unsigned long _cogl_debug_flags[COGL_DEBUG_N_LONGS];
GHashTable *_cogl_debug_instances;
static void
_cogl_parse_debug_string_for_keys (const char *value,
CoglBool enable,
const GDebugKey *keys,
unsigned int nkeys)
{
int long_num, key_num;
/* g_parse_debug_string expects the value field in GDebugKey to be a
mask in an unsigned int but the flags are stored in an array of
multiple longs so we need to build a separate array for each
possible unsigned int */
for (long_num = 0; long_num < COGL_DEBUG_N_LONGS; long_num++)
{
int int_num;
for (int_num = 0;
int_num < sizeof (unsigned long) / sizeof (unsigned int);
int_num++)
{
GDebugKey keys_for_int[sizeof (unsigned int) * 8];
int nkeys_for_int = 0;
for (key_num = 0; key_num < nkeys; key_num++)
{
int long_index = COGL_FLAGS_GET_INDEX (keys[key_num].value);
int int_index = (keys[key_num].value %
(sizeof (unsigned long) * 8) /
(sizeof (unsigned int) * 8));
if (long_index == long_num && int_index == int_num)
{
keys_for_int[nkeys_for_int] = keys[key_num];
keys_for_int[nkeys_for_int].value =
COGL_FLAGS_GET_MASK (keys[key_num].value) >>
(int_num * sizeof (unsigned int) * 8);
nkeys_for_int++;
}
}
if (nkeys_for_int > 0)
{
unsigned long mask =
((unsigned long) g_parse_debug_string (value,
keys_for_int,
nkeys_for_int)) <<
(int_num * sizeof (unsigned int) * 8);
if (enable)
_cogl_debug_flags[long_num] |= mask;
else
_cogl_debug_flags[long_num] &= ~mask;
}
}
}
}
void
_cogl_parse_debug_string (const char *value,
CoglBool enable,
CoglBool ignore_help)
{
if (ignore_help && strcmp (value, "help") == 0)
return;
/* We don't want to let g_parse_debug_string handle "all" because
* literally enabling all the debug options wouldn't be useful to
* anyone; instead the all option enables all non behavioural
* options.
*/
if (strcmp (value, "all") == 0 ||
strcmp (value, "verbose") == 0)
{
int i;
for (i = 0; i < n_cogl_log_debug_keys; i++)
if (enable)
COGL_DEBUG_SET_FLAG (cogl_log_debug_keys[i].value);
else
COGL_DEBUG_CLEAR_FLAG (cogl_log_debug_keys[i].value);
}
else if (g_ascii_strcasecmp (value, "help") == 0)
{
g_printerr ("\n\n%28s\n", _("Supported debug values:"));
#define OPT(MASK_NAME, GROUP, NAME, NAME_FORMATTED, DESCRIPTION) \
g_printerr ("%28s %s\n", NAME ":", g_dgettext (GETTEXT_PACKAGE, \
DESCRIPTION));
#include "cogl-debug-options.h"
g_printerr ("\n%28s\n", _("Special debug values:"));
OPT (IGNORED, "ignored", "all", "ignored", \
N_("Enables all non-behavioural debug options"));
OPT (IGNORED, "ignored", "verbose", "ignored", \
N_("Enables all non-behavioural debug options"));
#undef OPT
exit (1);
}
else
{
_cogl_parse_debug_string_for_keys (value,
enable,
cogl_log_debug_keys,
n_cogl_log_debug_keys);
_cogl_parse_debug_string_for_keys (value,
enable,
cogl_behavioural_debug_keys,
n_cogl_behavioural_debug_keys);
}
}
#ifdef COGL_ENABLE_DEBUG
static CoglBool
cogl_arg_debug_cb (const char *key,
const char *value,
void *user_data)
{
_cogl_parse_debug_string (value,
TRUE /* enable the flags */,
FALSE /* don't ignore help */);
return TRUE;
}
static CoglBool
cogl_arg_no_debug_cb (const char *key,
const char *value,
void *user_data)
{
_cogl_parse_debug_string (value,
FALSE, /* disable the flags */
TRUE /* ignore help */);
return TRUE;
}
#endif /* COGL_ENABLE_DEBUG */
static GOptionEntry cogl_args[] = {
#ifdef COGL_ENABLE_DEBUG
{ "cogl-debug", 0, 0, G_OPTION_ARG_CALLBACK, cogl_arg_debug_cb,
N_("Cogl debugging flags to set"), "FLAGS" },
{ "cogl-no-debug", 0, 0, G_OPTION_ARG_CALLBACK, cogl_arg_no_debug_cb,
N_("Cogl debugging flags to unset"), "FLAGS" },
#endif /* COGL_ENABLE_DEBUG */
{ NULL, },
};
void
_cogl_debug_check_environment (void)
{
const char *env_string;
env_string = g_getenv ("COGL_DEBUG");
if (env_string != NULL)
{
_cogl_parse_debug_string (env_string,
TRUE /* enable the flags */,
FALSE /* don't ignore help */);
env_string = NULL;
}
env_string = g_getenv ("COGL_NO_DEBUG");
if (env_string != NULL)
{
_cogl_parse_debug_string (env_string,
FALSE /* disable the flags */,
FALSE /* don't ignore help */);
env_string = NULL;
}
}
static CoglBool
pre_parse_hook (GOptionContext *context,
GOptionGroup *group,
void *data,
GError **error)
{
_cogl_init ();
return TRUE;
}
/* XXX: GOption based library initialization is not reliable because the
* GOption API has no way to represent dependencies between libraries.
*/
GOptionGroup *
cogl_get_option_group (void)
{
GOptionGroup *group;
group = g_option_group_new ("cogl",
_("Cogl Options"),
_("Show Cogl options"),
NULL, NULL);
g_option_group_set_parse_hooks (group, pre_parse_hook, NULL);
g_option_group_add_entries (group, cogl_args);
g_option_group_set_translation_domain (group, GETTEXT_PACKAGE);
return group;
}