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mutter-performance-source/cogl/cogl-debug-options.h
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

192 lines
6 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 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/>.
*
*
*/
OPT (OBJECT,
N_("Cogl Tracing"),
"ref-counts",
N_("CoglObject references"),
N_("Debug ref counting issues for CoglObjects"))
OPT (SLICING,
N_("Cogl Tracing"),
"slicing",
N_("Trace Texture Slicing"),
N_("debug the creation of texture slices"))
OPT (ATLAS,
N_("Cogl Tracing"),
"atlas",
N_("Trace Atlas Textures"),
N_("Debug texture atlas management"))
OPT (BLEND_STRINGS,
N_("Cogl Tracing"),
"blend-strings",
N_("Trace Blend Strings"),
N_("Debug CoglBlendString parsing"))
OPT (JOURNAL,
N_("Cogl Tracing"),
"journal",
N_("Trace Journal"),
N_("View all the geometry passing through the journal"))
OPT (BATCHING,
N_("Cogl Tracing"),
"batching",
N_("Trace Batching"),
N_("Show how geometry is being batched in the journal"))
OPT (MATRICES,
N_("Cogl Tracing"),
"matrices",
N_("Trace matrices"),
N_("Trace all matrix manipulation"))
/* XXX we should replace the "draw" option its very hand wavy... */
OPT (DRAW,
N_("Cogl Tracing"),
"draw",
N_("Trace Misc Drawing"),
N_("Trace some misc drawing operations"))
OPT (PANGO,
N_("Cogl Tracing"),
"pango",
N_("Trace Pango Renderer"),
N_("Trace the Cogl Pango renderer"))
OPT (TEXTURE_PIXMAP,
N_("Cogl Tracing"),
"texture-pixmap",
N_("Trace CoglTexturePixmap backend"),
N_("Trace the Cogl texture pixmap backend"))
OPT (RECTANGLES,
N_("Visualize"),
"rectangles",
N_("Outline rectangles"),
N_("Add wire outlines for all rectangular geometry"))
OPT (WIREFRAME,
N_("Visualize"),
"wireframe",
N_("Show wireframes"),
N_("Add wire outlines for all geometry"))
OPT (DISABLE_BATCHING,
N_("Root Cause"),
"disable-batching",
N_("Disable Journal batching"),
N_("Disable batching of geometry in the Cogl Journal."))
OPT (DISABLE_VBOS,
N_("Root Cause"),
"disable-vbos",
N_("Disable GL Vertex Buffers"),
N_("Disable use of OpenGL vertex buffer objects"))
OPT (DISABLE_PBOS,
N_("Root Cause"),
"disable-pbos",
N_("Disable GL Pixel Buffers"),
N_("Disable use of OpenGL pixel buffer objects"))
OPT (DISABLE_SOFTWARE_TRANSFORM,
N_("Root Cause"),
"disable-software-transform",
N_("Disable software rect transform"),
N_("Use the GPU to transform rectangular geometry"))
OPT (DUMP_ATLAS_IMAGE,
N_("Cogl Specialist"),
"dump-atlas-image",
N_("Dump atlas images"),
N_("Dump texture atlas changes to an image file"))
OPT (DISABLE_ATLAS,
N_("Root Cause"),
"disable-atlas",
N_("Disable texture atlasing"),
N_("Disable use of texture atlasing"))
OPT (DISABLE_SHARED_ATLAS,
N_("Root Cause"),
"disable-shared-atlas",
N_("Disable sharing the texture atlas between text and images"),
N_("When this is set the glyph cache will always use a separate texture "
"for its atlas. Otherwise it will try to share the atlas with images."))
OPT (DISABLE_TEXTURING,
N_("Root Cause"),
"disable-texturing",
N_("Disable texturing"),
N_("Disable texturing any primitives"))
OPT (DISABLE_ARBFP,
N_("Root Cause"),
"disable-arbfp",
N_("Disable arbfp"),
N_("Disable use of ARB fragment programs"))
OPT (DISABLE_FIXED,
N_("Root Cause"),
"disable-fixed",
N_("Disable fixed"),
N_("Disable use of the fixed function pipeline backend"))
OPT (DISABLE_GLSL,
N_("Root Cause"),
"disable-glsl",
N_("Disable GLSL"),
N_("Disable use of GLSL"))
OPT (DISABLE_BLENDING,
N_("Root Cause"),
"disable-blending",
N_("Disable blending"),
N_("Disable use of blending"))
OPT (DISABLE_NPOT_TEXTURES,
N_("Root Cause"),
"disable-npot-textures",
N_("Disable non-power-of-two textures"),
N_("Makes Cogl think that the GL driver doesn't support NPOT textures "
"so that it will create sliced textures or textures with waste instead."))
OPT (DISABLE_SOFTWARE_CLIP,
N_("Root Cause"),
"disable-software-clip",
N_("Disable software clipping"),
N_("Disables Cogl's attempts to clip some rectangles in software."))
OPT (SHOW_SOURCE,
N_("Cogl Tracing"),
"show-source",
N_("Show source"),
N_("Show generated ARBfp/GLSL source code"))
OPT (OPENGL,
N_("Cogl Tracing"),
"opengl",
N_("Trace some OpenGL"),
N_("Traces some select OpenGL calls"))
OPT (OFFSCREEN,
N_("Cogl Tracing"),
"offscreen",
N_("Trace offscreen support"),
N_("Debug offscreen support"))
OPT (DISABLE_BLENDING,
N_("Root Cause"),
"disable-program-caches",
N_("Disable program caches"),
N_("Disable fallback caches for arbfp and glsl programs"))
OPT (DISABLE_FAST_READ_PIXEL,
N_("Root Cause"),
"disable-fast-read-pixel",
N_("Disable read pixel optimization"),
N_("Disable optimization for reading 1px for simple "
"scenes of opaque rectangles"))
OPT (CLIPPING,
N_("Cogl Tracing"),
"clipping",
N_("Trace clipping"),
N_("Logs information about how Cogl is implementing clipping"))
OPT (PERFORMANCE,
N_("Cogl Tracing"),
"performance",
N_("Trace performance concerns"),
N_("Tries to highlight sub-optimal Cogl usage."))