mutter/clutter/cogl/common/cogl-vertex-buffer.c
Robert Bragg e338245827 Renames the mesh api to the "vertex buffer api".
This better reflects the fact that the api manages sets of vertex attributes,
and the attributes really have no implied form. It is only when you use the
attributes to draw that they become mesh like; when you specify how they should
be interpreted, e.g. as triangle lists or fans etc. This rename frees up the
term "mesh", which can later be applied to a concept slightly more fitting.
E.g. at some point it would be nice to have a higher level abstraction that
sits on top of cogl vertex buffers that adds the concept of faces. (Somthing
like Blender's mesh objects.) There have also been some discussions over
particle engines, and these can be defined in terms of emitter faces; so some
other kind of mesh abstraction might be usefull here.
2009-01-20 22:29:35 +00:00

1634 lines
51 KiB
C

/*
* Cogl.
*
* An OpenGL/GLES Abstraction/Utility Layer
*
* Vertex Buffer API: Handle extensible arrays of vertex attributes
*
* Copyright (C) 2008 Intel Corporation.
*
* Authored by: Robert Bragg <robert@linux.intel.com>
*
* 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/>.
*/
/* XXX: For an overview of the functionality implemented here, please
* see cogl-vertex-buffer.h, which contains the gtk-doc section overview
* for the Vertex Buffers API.
*/
/*
* TODO: We need to do a better job of minimizing when we call glVertexPointer
* and pals in enable_state_for_drawing_attributes_buffer
*
* We should have an internal 2-tuple cache of (VBO, offset) for each of them
* so we can avoid some GL calls. We could have cogl wrappers for the
* gl*Pointer funcs that look like this:
*
* cogl_vertex_pointer (n_components, gl_type, stride, vbo, offset);
* cogl_color_pointer (n_components, gl_type, stride, vbo, offset);
*
* They would also accept NULL for the VBO handle to support old style vertex
* arrays.
*
* TODO:
* Actually hook this up to the cogl shaders infrastructure. The vertex
* buffer API has been designed to allow adding of arbitrary attributes for use
* with shaders, but this has yet to be actually plumbed together and tested.
* The bits we are missing:
* - cogl_program_use doesn't currently record within ctx-> which program
* is currently in use so a.t.m only Clutter knows the current shader.
* - We don't query the current shader program for the generic vertex indices
* (using glGetAttribLocation) so that we can call glEnableVertexAttribArray
* with those indices.
* (currently we just make up consecutive indices)
* - some dirty flag mechanims to know when the shader program has changed
* so we don't need to re-query it each time we draw a buffer.
*
* TODO:
* There is currently no API for querying back info about a buffer, E.g.:
* cogl_vertex_buffer_get_n_vertices (buffer_handle);
* cogl_vertex_buffer_get_n_components (buffer_handle, "attrib_name");
* cogl_vertex_buffer_get_stride (buffer_handle, "attrib_name");
* cogl_vertex_buffer_get_normalized (buffer_handle, "attrib_name");
* cogl_vertex_buffer_map (buffer_handle, "attrib_name");
* cogl_vertex_buffer_unmap (buffer_handle, "attrib_name");
* (Realistically I wouldn't expect anyone to use such an API to examine the
* contents of a buffer for modification, since you'd need to handle too many
* possibilities, but never the less there might be other value in these.)
* TODO:
* It may be worth exposing the underlying VBOs for some advanced use
* cases, e.g.:
* handle = cogl_vbo_new (COGL_VBO_FLAG_STATIC);
* pointer = cogl_vbo_map (handle, COGL_VBO_FLAG_WRITEONLY);
* cogl_vbo_unmap (handle);
* cogl_vbo_set_data (handle, size, data);
* cogl_vbo_set_sub_data (handle, offset, size, data);
* cogl_vbo_set_usage_hint (COGL_VBO_FLAG_DYNAMIC);
*
* TODO:
* Experiment with wider use of the vertex buffers API internally to Cogl.
* - There is potential, I think, for this API to become a work-horse API
* within COGL for submitting geometry to the GPU, and could unify some of
* the GL/GLES code paths.
* E.g.:
* - Try creating a per-context vertex buffer cache for cogl_texture_rectangle
* to sit on top of.
* - Try saving the tesselation of paths/polygons into vertex buffers
* internally.
*
* TODO
* Expose API that lets developers get back a buffer handle for a particular
* polygon so they may add custom attributes to them.
* - It should be possible to query/modify attributes efficiently, in place,
* avoiding copies. It would not be acceptable to simply require that
* developers must query back the n_vertices of a buffer and then the
* n_components, type and stride etc of each attribute since there
* would be too many combinations to realistically handle.
*
* - In practice, some cases might be best solved with a higher level
* EditableMesh API, (see futher below) but for many cases I think an
* API like this might be appropriate:
*
* cogl_vertex_buffer_foreach_vertex (buffer_handle,
* (AttributesBufferIteratorFunc)callback,
* "gl_Vertex", "gl_Color", NULL);
* static void callback (CoglVertexBufferVertex *vert)
* {
* GLfloat *pos = vert->attrib[0];
* GLubyte *color = vert->attrib[1];
* GLfloat *new_attrib = buf[vert->index];
*
* new_attrib = pos*color;
* }
*
* TODO
* Think about a higher level Mesh API for building/modifying attribute buffers
* - E.g. look at Blender for inspiration here. They can build a mesh from
* "MVert", "MFace" and "MEdge" primitives.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdio.h>
#include <string.h>
#include <glib/gprintf.h>
#include "cogl.h"
#include "cogl-internal.h"
#include "cogl-util.h"
#include "cogl-context.h"
#include "cogl-handle.h"
#include "cogl-vertex-buffer-private.h"
#define PAD_FOR_ALIGNMENT(VAR, TYPE_SIZE) \
(VAR = TYPE_SIZE + ((VAR - 1) & ~(TYPE_SIZE - 1)))
/*
* GL/GLES compatability defines for VBO thingies:
*/
#if defined (HAVE_COGL_GL)
#define glGenBuffers ctx->pf_glGenBuffersARB
#define glBindBuffer ctx->pf_glBindBufferARB
#define glBufferData ctx->pf_glBufferDataARB
#define glBufferSubData ctx->pf_glBufferSubDataARB
#define glDeleteBuffers ctx->pf_glDeleteBuffersARB
#define glMapBuffer ctx->pf_glMapBufferARB
#define glUnmapBuffer ctx->pf_glUnmapBufferARB
#ifndef GL_ARRAY_BUFFER
#define GL_ARRAY_BUFFER GL_ARRAY_BUFFER_ARB
#endif
#elif defined (HAVE_COGL_GLES2)
#define glVertexPointer cogl_wrap_glVertexPointer
#define glNormalPointer cogl_wrap_glNormalPointer
#define glTexCoordPointer cogl_wrap_glTexCoordPointer
#define glColorPointer cogl_wrap_glColorPointer
#define glDrawArrays cogl_wrap_glDrawArrays
#define glEnableClientState cogl_wrap_glEnableClientState
#define glDisableClientState cogl_wrap_glDisableClientState
#endif
/*
* GL/GLES compatability defines for shader things:
*/
#if defined (HAVE_COGL_GL)
#define glVertexAttribPointer ctx->pf_glVertexAttribPointerARB
#define glEnableVertexAttribArray ctx->pf_glEnableVertexAttribArrayARB
#define glDisableVertexAttribArray ctx->pf_glEnableVertexAttribArrayARB
#define MAY_HAVE_PROGRAMABLE_GL
#elif defined (HAVE_COGL_GLES2)
/* NB: GLES2 had shaders in core since day one so again we don't need
* defines in this case: */
#define MAY_HAVE_PROGRAMABLE_GL
#endif
#ifndef HAVE_COGL_GL
/* GLES doesn't have glDrawRangeElements, so we simply pretend it does
* but that it makes no use of the start, end constraints: */
#define glDrawRangeElements(mode, start, end, count, type, indices) \
glDrawElements (mode, count, type, indices)
#else /* HAVE_COGL_GL */
#define glDrawRangeElements(mode, start, end, count, type, indices) \
ctx->pf_glDrawRangeElements (mode, start, end, count, type, indices)
#endif /* HAVE_COGL_GL */
static void _cogl_vertex_buffer_free (CoglVertexBuffer *buffer);
COGL_HANDLE_DEFINE (VertexBuffer,
vertex_buffer,
vertex_buffer_handles);
CoglHandle
cogl_vertex_buffer_new (guint n_vertices)
{
CoglVertexBuffer *buffer = g_slice_alloc (sizeof (CoglVertexBuffer));
buffer->ref_count = 1;
COGL_HANDLE_DEBUG_NEW (CoglVertexBuffer, buffer);
buffer->n_vertices = n_vertices;
buffer->submitted_vbos = NULL;
buffer->new_attributes = NULL;
/* return COGL_INVALID_HANDLE; */
return _cogl_vertex_buffer_handle_new (buffer);
}
/* There are a number of standard OpenGL attributes that we deal with
* specially. These attributes are all namespaced with a "gl_" prefix
* so we should catch any typos instead of silently adding a custom
* attribute.
*/
static CoglVertexBufferAttribFlags
validate_gl_attribute (const char *gl_attribute,
guint8 *n_components,
guint8 *texture_unit)
{
CoglVertexBufferAttribFlags type;
char *detail_seperator = NULL;
int name_len;
detail_seperator = strstr (gl_attribute, "::");
if (detail_seperator)
name_len = detail_seperator - gl_attribute;
else
name_len = strlen (gl_attribute);
if (strncmp (gl_attribute, "Vertex", name_len) == 0)
{
type = COGL_VERTEX_BUFFER_ATTRIB_FLAG_VERTEX_ARRAY;
}
else if (strncmp (gl_attribute, "Color", name_len) == 0)
{
type = COGL_VERTEX_BUFFER_ATTRIB_FLAG_COLOR_ARRAY;
}
else if (strncmp (gl_attribute,
"MultiTexCoord",
strlen ("MultiTexCoord")) == 0)
{
unsigned int unit;
if (sscanf (gl_attribute, "MultiTexCoord%u", &unit) != 1)
{
g_warning ("gl_MultiTexCoord attributes should include a\n"
"texture unit number, E.g. gl_MultiTexCoord0\n");
unit = 0;
}
/* FIXME: validate any '::' delimiter for this case */
*texture_unit = unit;
type = COGL_VERTEX_BUFFER_ATTRIB_FLAG_TEXTURE_COORD_ARRAY;
}
else if (strncmp (gl_attribute, "Normal", name_len) == 0)
{
*n_components = 1;
type = COGL_VERTEX_BUFFER_ATTRIB_FLAG_NORMAL_ARRAY;
}
else
{
g_warning ("Unknown gl_* attribute name gl_%s\n", gl_attribute);
type = COGL_VERTEX_BUFFER_ATTRIB_FLAG_INVALID;
}
return type;
}
/* This validates that a custom attribute name is a valid GLSL variable name
*
* NB: attribute names may have a detail component delimited using '::' E.g.
* custom_attrib::foo or custom_attrib::bar
*
* maybe I should hang a compiled regex somewhere to handle this
*/
static gboolean
validate_custom_attribute_name (const char *attribute_name)
{
char *detail_seperator = NULL;
int name_len;
int i;
detail_seperator = strstr (attribute_name, "::");
if (detail_seperator)
name_len = detail_seperator - attribute_name;
else
name_len = strlen (attribute_name);
if (name_len == 0
|| !g_ascii_isalpha (attribute_name[0])
|| attribute_name[0] != '_')
return FALSE;
for (i = 1; i < name_len; i++)
if (!g_ascii_isalnum (attribute_name[i]) || attribute_name[i] != '_')
return FALSE;
return TRUE;
}
/* Iterates the CoglVertexBufferVBOs of a buffer and creates a flat list
* of all the submitted attributes
*
* Note: The CoglVertexBufferAttrib structs are deep copied.
*/
static GList *
copy_submitted_attributes_list (CoglVertexBuffer *buffer)
{
GList *tmp;
GList *submitted_attributes = NULL;
for (tmp = buffer->submitted_vbos; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferVBO *cogl_vbo = tmp->data;
GList *tmp2;
for (tmp2 = cogl_vbo->attributes; tmp2 != NULL; tmp2 = tmp2->next)
{
CoglVertexBufferAttrib *attribute = tmp2->data;
CoglVertexBufferAttrib *copy =
g_slice_alloc (sizeof (CoglVertexBufferAttrib));
*copy = *attribute;
submitted_attributes = g_list_prepend (submitted_attributes, copy);
}
}
return submitted_attributes;
}
static CoglVertexBufferAttribFlags
get_attribute_gl_type_flag_from_gl_type (GLenum gl_type)
{
switch (gl_type)
{
case GL_BYTE:
return COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_BYTE;
case GL_UNSIGNED_BYTE:
return COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_UNSIGNED_BYTE;
case GL_SHORT:
return COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_SHORT;
case GL_UNSIGNED_SHORT:
return COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_UNSIGNED_SHORT;
case GL_FLOAT:
return COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_FLOAT;
#if HAVE_COGL_GL
case GL_INT:
return COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_INT;
case GL_UNSIGNED_INT:
return COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_UNSIGNED_INT;
case GL_DOUBLE:
return COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_DOUBLE;
#endif
default:
g_warning ("Attribute Buffers API: "
"Unrecognised OpenGL type enum 0x%08x\n", gl_type);
return 0;
}
}
static gsize
get_gl_type_size (CoglVertexBufferAttribFlags flags)
{
CoglVertexBufferAttribFlags gl_type =
flags & COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_MASK;
switch (gl_type)
{
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_BYTE:
return sizeof (GLbyte);
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_UNSIGNED_BYTE:
return sizeof (GLubyte);
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_SHORT:
return sizeof (GLshort);
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_UNSIGNED_SHORT:
return sizeof (GLushort);
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_FLOAT:
return sizeof (GLfloat);
#if HAVE_COGL_GL
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_INT:
return sizeof (GLint);
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_UNSIGNED_INT:
return sizeof (GLuint);
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_DOUBLE:
return sizeof (GLdouble);
#endif
default:
g_warning ("Mesh API: Unrecognised OpenGL type enum 0x%08x\n", gl_type);
return 0;
}
}
void
cogl_vertex_buffer_add (CoglHandle handle,
const char *attribute_name,
guint8 n_components,
GLenum gl_type,
gboolean normalized,
guint16 stride,
const void *pointer)
{
CoglVertexBuffer *buffer;
GQuark name_quark = g_quark_from_string (attribute_name);
gboolean modifying_an_attrib = FALSE;
CoglVertexBufferAttrib *attribute;
CoglVertexBufferAttribFlags flags = 0;
guint8 texture_unit = 0;
GList *tmp;
if (!cogl_is_vertex_buffer (handle))
return;
buffer = _cogl_vertex_buffer_pointer_from_handle (handle);
/* The submit function works by diffing between submitted_attributes
* and new_attributes to minimize the upload bandwidth + cost of
* allocating new VBOs, so if there isn't already a list of new_attributes
* we create one: */
if (!buffer->new_attributes)
buffer->new_attributes = copy_submitted_attributes_list (buffer);
/* Note: we first look for an existing attribute that we are modifying
* so we may skip needing to validate the name */
for (tmp = buffer->new_attributes; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferAttrib *submitted_attribute = tmp->data;
if (submitted_attribute->name == name_quark)
{
modifying_an_attrib = TRUE;
attribute = submitted_attribute;
/* since we will skip validate_gl_attribute in this case, we need
* to pluck out the attribute type before overwriting the flags: */
flags |=
attribute->flags & COGL_VERTEX_BUFFER_ATTRIB_FLAG_TYPE_MASK;
break;
}
}
if (!modifying_an_attrib)
{
/* Validate the attribute name, is suitable as a variable name */
if (strncmp (attribute_name, "gl_", 3) == 0)
{
flags |= validate_gl_attribute (attribute_name + 3,
&n_components,
&texture_unit);
if (flags & COGL_VERTEX_BUFFER_ATTRIB_FLAG_INVALID)
return;
}
else
{
flags |= COGL_VERTEX_BUFFER_ATTRIB_FLAG_CUSTOM_ARRAY;
if (validate_custom_attribute_name (attribute_name))
return;
}
attribute = g_slice_alloc (sizeof (CoglVertexBufferAttrib));
}
attribute->name = g_quark_from_string (attribute_name);
attribute->n_components = n_components;
attribute->stride = buffer->n_vertices > 1 ? stride : 0;
attribute->u.pointer = pointer;
attribute->texture_unit = texture_unit;
flags |= get_attribute_gl_type_flag_from_gl_type (gl_type);
flags |= COGL_VERTEX_BUFFER_ATTRIB_FLAG_ENABLED;
/* Note: We currently just assume, if an attribute is *ever* updated
* then it should be taged as frequently changing. */
if (modifying_an_attrib)
flags |= COGL_VERTEX_BUFFER_ATTRIB_FLAG_FREQUENT_RESUBMIT;
else
flags |= COGL_VERTEX_BUFFER_ATTRIB_FLAG_INFREQUENT_RESUBMIT;
if (normalized)
flags |= COGL_VERTEX_BUFFER_ATTRIB_FLAG_NORMALIZED;
attribute->flags = flags;
/* NB: get_gl_type_size must be called after setting the type
* flags, above. */
if (attribute->stride)
attribute->span_bytes = buffer->n_vertices * attribute->stride;
else
attribute->span_bytes = buffer->n_vertices
* attribute->n_components
* get_gl_type_size (attribute->flags);
if (!modifying_an_attrib)
buffer->new_attributes =
g_list_prepend (buffer->new_attributes, attribute);
}
void
cogl_vertex_buffer_delete (CoglHandle handle,
const char *attribute_name)
{
CoglVertexBuffer *buffer;
GQuark name = g_quark_from_string (attribute_name);
GList *tmp;
if (!cogl_is_vertex_buffer (handle))
return;
buffer = _cogl_vertex_buffer_pointer_from_handle (handle);
/* The submit function works by diffing between submitted_attributes
* and new_attributes to minimize the upload bandwidth + cost of
* allocating new VBOs, so if there isn't already a list of new_attributes
* we create one: */
if (!buffer->new_attributes)
buffer->new_attributes = copy_submitted_attributes_list (buffer);
for (tmp = buffer->new_attributes; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferAttrib *submitted_attribute = tmp->data;
if (submitted_attribute->name == name)
{
buffer->new_attributes =
g_list_delete_link (buffer->new_attributes, tmp);
g_slice_free (CoglVertexBufferAttrib, submitted_attribute);
return;
}
}
g_warning ("Failed to find an attribute named %s to delete\n",
attribute_name);
}
static void
set_attribute_enable (CoglHandle handle,
const char *attribute_name,
gboolean state)
{
CoglVertexBuffer *buffer;
GQuark name_quark = g_quark_from_string (attribute_name);
GList *tmp;
if (!cogl_is_vertex_buffer (handle))
return;
buffer = _cogl_vertex_buffer_pointer_from_handle (handle);
/* NB: If a buffer is currently being edited, then there can be two seperate
* lists of attributes; those that are currently submitted and a new list yet
* to be submitted, we need to modify both. */
for (tmp = buffer->new_attributes; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferAttrib *attribute = tmp->data;
if (attribute->name == name_quark)
{
if (state)
attribute->flags |= COGL_VERTEX_BUFFER_ATTRIB_FLAG_ENABLED;
else
attribute->flags &= ~COGL_VERTEX_BUFFER_ATTRIB_FLAG_ENABLED;
break;
}
}
for (tmp = buffer->submitted_vbos; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferVBO *cogl_vbo = tmp->data;
GList *tmp2;
for (tmp2 = cogl_vbo->attributes; tmp2 != NULL; tmp2 = tmp2->next)
{
CoglVertexBufferAttrib *attribute = tmp2->data;
if (attribute->name == name_quark)
{
if (state)
attribute->flags |= COGL_VERTEX_BUFFER_ATTRIB_FLAG_ENABLED;
else
attribute->flags &= ~COGL_VERTEX_BUFFER_ATTRIB_FLAG_ENABLED;
return;
}
}
}
g_warning ("Failed to find an attribute named %s to %s\n",
attribute_name,
state == TRUE ? "enable" : "disable");
}
void
cogl_vertex_buffer_enable (CoglHandle handle,
const char *attribute_name)
{
set_attribute_enable (handle, attribute_name, TRUE);
}
void
cogl_vertex_buffer_disable (CoglHandle handle,
const char *attribute_name)
{
set_attribute_enable (handle, attribute_name, FALSE);
}
static void
cogl_vertex_buffer_attribute_free (CoglVertexBufferAttrib *attribute)
{
g_slice_free (CoglVertexBufferAttrib, attribute);
}
/* Given an attribute that we know has already been submitted before, this
* function looks for the existing VBO that contains it.
*
* Note: It will free redundant attribute struct once the corresponding
* VBO has been found.
*/
static void
filter_already_submitted_attribute (CoglVertexBufferAttrib *attribute,
GList **reuse_vbos,
GList **submitted_vbos)
{
GList *tmp;
/* First check the cogl_vbos we already know are being reused since we
* are more likley to get a match here */
for (tmp = *reuse_vbos; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferVBO *cogl_vbo = tmp->data;
GList *tmp2;
for (tmp2 = cogl_vbo->attributes; tmp2 != NULL; tmp2 = tmp2->next)
{
CoglVertexBufferAttrib *vbo_attribute = tmp2->data;
if (vbo_attribute->name == attribute->name)
{
vbo_attribute->flags &=
~COGL_VERTEX_BUFFER_ATTRIB_FLAG_UNUSED;
/* Note: we don't free the redundant attribute here, since it
* will be freed after all filtering in
* cogl_vertex_buffer_submit */
return;
}
}
}
for (tmp = *submitted_vbos; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferVBO *cogl_vbo = tmp->data;
CoglVertexBufferAttrib *reuse_attribute = NULL;
GList *tmp2;
for (tmp2 = cogl_vbo->attributes; tmp2 != NULL; tmp2 = tmp2->next)
{
CoglVertexBufferAttrib *vbo_attribute = tmp2->data;
if (vbo_attribute->name == attribute->name)
{
reuse_attribute = vbo_attribute;
/* Note: we don't free the redundant attribute here, since it
* will be freed after all filtering in
* cogl_vertex_buffer_submit */
*submitted_vbos = g_list_remove_link (*submitted_vbos, tmp);
tmp->next = *reuse_vbos;
*reuse_vbos = tmp;
break;
}
}
if (!reuse_attribute)
continue;
/* Mark all but the matched attribute as UNUSED, so that when we
* finish filtering all our attributes any attrributes still
* marked as UNUSED can be removed from the their cogl_vbo */
for (tmp2 = cogl_vbo->attributes; tmp2 != NULL; tmp2 = tmp2->next)
{
CoglVertexBufferAttrib *vbo_attribute = tmp2->data;
if (vbo_attribute != reuse_attribute)
vbo_attribute->flags |= COGL_VERTEX_BUFFER_ATTRIB_FLAG_UNUSED;
}
return;
}
g_critical ("Failed to find the cogl vbo that corresponds to an\n"
"attribute that had apparently already been submitted!");
}
/* When we first mark a CoglVertexBufferVBO to be reused, we mark the
* attributes as unsed, so that when filtering of attributes into VBOs is done
* we can then prune the now unsed attributes. */
static void
remove_unused_attributes (CoglVertexBufferVBO *cogl_vbo)
{
GList *tmp;
GList *next;
for (tmp = cogl_vbo->attributes; tmp != NULL; tmp = next)
{
CoglVertexBufferAttrib *attribute = tmp->data;
next = tmp->next;
if (attribute->flags & COGL_VERTEX_BUFFER_ATTRIB_FLAG_UNUSED)
{
cogl_vbo->attributes =
g_list_delete_link (cogl_vbo->attributes, tmp);
g_slice_free (CoglVertexBufferAttrib, attribute);
}
}
}
/* Give a newly added, strided, attribute, this function looks for a
* CoglVertexBufferVBO that the attribute is interleved with. If it can't
* find one then a new CoglVertexBufferVBO is allocated and added to the
* list of new_strided_vbos.
*/
static void
filter_strided_attribute (CoglVertexBufferAttrib *attribute,
GList **new_vbos)
{
GList *tmp;
CoglVertexBufferVBO *new_cogl_vbo;
for (tmp = *new_vbos; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferVBO *cogl_vbo = tmp->data;
GList *tmp2;
if (!cogl_vbo->flags & COGL_VERTEX_BUFFER_VBO_FLAG_STRIDED)
continue;
for (tmp2 = cogl_vbo->attributes; tmp2 != NULL; tmp2 = tmp2->next)
{
CoglVertexBufferAttrib *vbo_attribute = tmp2->data;
const char *attribute_start = attribute->u.pointer;
const char *vbo_attribute_start = vbo_attribute->u.pointer;
/* NB: All attributes have buffer->n_vertices values which
* simplifies determining which attributes are interleved
* since we assume they will start no farther than +- a
* stride away from each other:
*/
if (attribute_start <= (vbo_attribute_start - vbo_attribute->stride)
|| attribute_start
>= (vbo_attribute_start + vbo_attribute->stride))
continue; /* Not interleved */
cogl_vbo->attributes =
g_list_prepend (cogl_vbo->attributes, attribute);
if (attribute->flags &
COGL_VERTEX_BUFFER_ATTRIB_FLAG_FREQUENT_RESUBMIT)
{
cogl_vbo->flags &=
~COGL_VERTEX_BUFFER_VBO_FLAG_INFREQUENT_RESUBMIT;
cogl_vbo->flags |=
COGL_VERTEX_BUFFER_VBO_FLAG_FREQUENT_RESUBMIT;
}
return;
}
}
new_cogl_vbo = g_slice_alloc (sizeof (CoglVertexBufferVBO));
new_cogl_vbo->vbo_name = 0;
new_cogl_vbo->attributes = NULL;
new_cogl_vbo->attributes =
g_list_prepend (new_cogl_vbo->attributes, attribute);
/* Any one of the interleved attributes will have the same span_bytes */
new_cogl_vbo->vbo_bytes = attribute->span_bytes;
new_cogl_vbo->flags = COGL_VERTEX_BUFFER_VBO_FLAG_STRIDED;
if (attribute->flags & COGL_VERTEX_BUFFER_ATTRIB_FLAG_INFREQUENT_RESUBMIT)
new_cogl_vbo->flags |= COGL_VERTEX_BUFFER_VBO_FLAG_INFREQUENT_RESUBMIT;
else
new_cogl_vbo->flags |= COGL_VERTEX_BUFFER_VBO_FLAG_FREQUENT_RESUBMIT;
*new_vbos = g_list_prepend (*new_vbos, new_cogl_vbo);
return;
}
/* This iterates through the list of submitted VBOs looking for one that
* contains attribute. If found the list *link* is removed and returned */
static GList *
unlink_submitted_vbo_containing_attribute (GList **submitted_vbos,
CoglVertexBufferAttrib *attribute)
{
GList *tmp;
GList *next = NULL;
for (tmp = *submitted_vbos; tmp != NULL; tmp = next)
{
CoglVertexBufferVBO *submitted_vbo = tmp->data;
GList *tmp2;
next = tmp->next;
for (tmp2 = submitted_vbo->attributes; tmp2 != NULL; tmp2 = tmp2->next)
{
CoglVertexBufferAttrib *submitted_attribute = tmp2->data;
if (submitted_attribute->name == attribute->name)
{
*submitted_vbos = g_list_remove_link (*submitted_vbos, tmp);
return tmp;
}
}
}
return NULL;
}
/* Unlinks all the submitted VBOs that conflict with the new cogl_vbo and
* returns them as a list. */
static GList *
get_submitted_vbo_conflicts (GList **submitted_vbos,
CoglVertexBufferVBO *cogl_vbo)
{
GList *tmp;
GList *conflicts = NULL;
for (tmp = cogl_vbo->attributes; tmp != NULL; tmp = tmp->next)
{
GList *link =
unlink_submitted_vbo_containing_attribute (submitted_vbos,
tmp->data);
if (link)
{
/* prepend the link to the list of conflicts: */
link->next = conflicts;
conflicts = link;
}
}
return conflicts;
}
/* Any attributes in cogl_vbo gets removed from conflict_vbo */
static void
disassociate_conflicting_attributes (CoglVertexBufferVBO *conflict_vbo,
CoglVertexBufferVBO *cogl_vbo)
{
GList *tmp;
/* NB: The attributes list in conflict_vbo will be shrinking so
* we iterate those in the inner loop. */
for (tmp = cogl_vbo->attributes; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferAttrib *attribute = tmp->data;
GList *tmp2;
for (tmp2 = conflict_vbo->attributes; tmp2 != NULL; tmp2 = tmp2->next)
{
CoglVertexBufferAttrib *conflict_attribute = tmp2->data;
if (conflict_attribute->name == attribute->name)
{
cogl_vertex_buffer_attribute_free (conflict_attribute);
conflict_vbo->attributes =
g_list_delete_link (conflict_vbo->attributes, tmp2);
break;
}
}
}
}
static void
cogl_vertex_buffer_vbo_free (CoglVertexBufferVBO *cogl_vbo,
gboolean delete_gl_vbo)
{
GList *tmp;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
for (tmp = cogl_vbo->attributes; tmp != NULL; tmp = tmp->next)
{
cogl_vertex_buffer_attribute_free (tmp->data);
}
g_list_free (cogl_vbo->attributes);
if (delete_gl_vbo && cogl_vbo->flags &
COGL_VERTEX_BUFFER_VBO_FLAG_SUBMITTED)
GE (glDeleteBuffers (1, &cogl_vbo->vbo_name));
g_slice_free (CoglVertexBufferVBO, cogl_vbo);
}
/* This figures out the lowest attribute client pointer. (This pointer is used
* to upload all the interleved attributes).
*
* In the process it also replaces the client pointer with the attributes
* offset, and marks the attribute as submitted.
*/
static const void *
prep_strided_vbo_for_upload (CoglVertexBufferVBO *cogl_vbo)
{
GList *tmp;
const char *lowest_pointer = NULL;
for (tmp = cogl_vbo->attributes; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferAttrib *attribute = tmp->data;
const char *client_pointer = attribute->u.pointer;
if (!lowest_pointer || client_pointer < lowest_pointer)
lowest_pointer = client_pointer;
}
for (tmp = cogl_vbo->attributes; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferAttrib *attribute = tmp->data;
const char *client_pointer = attribute->u.pointer;
attribute->u.vbo_offset = client_pointer - lowest_pointer;
attribute->flags |= COGL_VERTEX_BUFFER_ATTRIB_FLAG_SUBMITTED;
}
return lowest_pointer;
}
static gboolean
upload_multipack_vbo_via_map_buffer (CoglVertexBufferVBO *cogl_vbo)
{
#if HAVE_COGL_GL
GList *tmp;
guint offset = 0;
char *buf;
_COGL_GET_CONTEXT (ctx, FALSE);
buf = glMapBuffer (GL_ARRAY_BUFFER, GL_WRITE_ONLY);
glGetError();
if (!buf)
return FALSE;
for (tmp = cogl_vbo->attributes; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferAttrib *attribute = tmp->data;
gsize attribute_size = attribute->span_bytes;
gsize gl_type_size = get_gl_type_size (attribute->flags);
PAD_FOR_ALIGNMENT (offset, gl_type_size);
memcpy (buf + offset, attribute->u.pointer, attribute_size);
attribute->u.vbo_offset = offset;
attribute->flags |= COGL_VERTEX_BUFFER_ATTRIB_FLAG_SUBMITTED;
offset += attribute_size;
}
glUnmapBuffer (GL_ARRAY_BUFFER);
return TRUE;
#else
return FALSE;
#endif
}
static void
upload_multipack_vbo_via_buffer_sub_data (CoglVertexBufferVBO *cogl_vbo)
{
GList *tmp;
guint offset = 0;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
for (tmp = cogl_vbo->attributes; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferAttrib *attribute = tmp->data;
gsize attribute_size = attribute->span_bytes;
gsize gl_type_size = get_gl_type_size (attribute->flags);
PAD_FOR_ALIGNMENT (offset, gl_type_size);
GE (glBufferSubData (GL_ARRAY_BUFFER,
offset,
attribute_size,
attribute->u.pointer));
attribute->u.vbo_offset = offset;
attribute->flags |= COGL_VERTEX_BUFFER_ATTRIB_FLAG_SUBMITTED;
offset += attribute_size;
}
}
static void
upload_gl_vbo (CoglVertexBufferVBO *cogl_vbo)
{
GLenum usage;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
g_return_if_fail (cogl_vbo->vbo_name != 0);
if (cogl_vbo->flags & COGL_VERTEX_BUFFER_VBO_FLAG_FREQUENT_RESUBMIT)
usage = GL_DYNAMIC_DRAW;
else
usage = GL_STATIC_DRAW;
GE (glBindBuffer (GL_ARRAY_BUFFER, cogl_vbo->vbo_name));
if (cogl_vbo->flags & COGL_VERTEX_BUFFER_VBO_FLAG_STRIDED)
{
const void *pointer =
prep_strided_vbo_for_upload (cogl_vbo);
GE (glBufferData (GL_ARRAY_BUFFER,
cogl_vbo->vbo_bytes,
pointer,
usage));
}
else if (cogl_vbo->flags & COGL_VERTEX_BUFFER_VBO_FLAG_MULTIPACK)
{
/* First we make it obvious to the driver that we want to update the
* whole buffer (without this, the driver is more likley to block
* if the GPU is busy using the buffer) */
GE (glBufferData (GL_ARRAY_BUFFER,
cogl_vbo->vbo_bytes,
NULL,
usage));
/* I think it might depend on the specific driver/HW whether its better
* to use glMapBuffer here or glBufferSubData here. There is even a good
* thread about this topic here:
* http://www.mail-archive.com/dri-devel@lists.sourceforge.net/msg35004.html
* For now I have gone with glMapBuffer, but the jury is still out.
*/
if (!upload_multipack_vbo_via_map_buffer (cogl_vbo))
upload_multipack_vbo_via_buffer_sub_data (cogl_vbo);
}
else
{
CoglVertexBufferAttrib *attribute = cogl_vbo->attributes->data;
GE (glBufferData (GL_ARRAY_BUFFER,
cogl_vbo->vbo_bytes,
attribute->u.pointer,
usage));
/* We forget this pointer now since the client will be free
* to re-use this memory */
attribute->u.pointer = NULL;
attribute->flags |= COGL_VERTEX_BUFFER_ATTRIB_FLAG_SUBMITTED;
}
cogl_vbo->flags |= COGL_VERTEX_BUFFER_VBO_FLAG_SUBMITTED;
GE (glBindBuffer (GL_ARRAY_BUFFER, 0));
}
/* Note: although there ends up being quite a few inner loops involved with
* resolving buffers, the number of attributes will be low so I don't expect
* them to cause a problem. */
static void
cogl_vertex_buffer_vbo_resolve (CoglVertexBuffer *buffer,
CoglVertexBufferVBO *new_cogl_vbo,
GList **final_vbos)
{
GList *conflicts;
GList *tmp;
GList *next;
gboolean found_target_vbo = FALSE;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
conflicts =
get_submitted_vbo_conflicts (&buffer->submitted_vbos, new_cogl_vbo);
for (tmp = conflicts; tmp != NULL; tmp = next)
{
CoglVertexBufferVBO *conflict_vbo = tmp->data;
next = tmp->next;
disassociate_conflicting_attributes (conflict_vbo, new_cogl_vbo);
if (!conflict_vbo->attributes)
{
/* See if we can re-use this now empty VBO: */
if (!found_target_vbo
&& conflict_vbo->vbo_bytes == new_cogl_vbo->vbo_bytes)
{
found_target_vbo = TRUE;
new_cogl_vbo->vbo_name = conflict_vbo->vbo_name;
cogl_vertex_buffer_vbo_free (conflict_vbo, FALSE);
upload_gl_vbo (new_cogl_vbo);
*final_vbos = g_list_prepend (*final_vbos, new_cogl_vbo);
}
else
cogl_vertex_buffer_vbo_free (conflict_vbo, TRUE);
}
else
{
/* Relink the VBO back into buffer->submitted_vbos since it may
* be involved in other conflicts later */
tmp->next = buffer->submitted_vbos;
tmp->prev = NULL;
buffer->submitted_vbos = tmp;
}
}
if (!found_target_vbo)
{
GE (glGenBuffers (1, &new_cogl_vbo->vbo_name));
/* FIXME: debug */
g_assert (glGetError() == GL_NO_ERROR);
upload_gl_vbo (new_cogl_vbo);
*final_vbos = g_list_prepend (*final_vbos, new_cogl_vbo);
}
}
void
cogl_vertex_buffer_submit (CoglHandle handle)
{
CoglVertexBuffer *buffer;
GList *tmp;
CoglVertexBufferVBO *new_multipack_vbo;
GList *new_multipack_vbo_link;
GList *new_vbos = NULL;
GList *reuse_vbos = NULL;
GList *final_vbos = NULL;
if (!cogl_is_vertex_buffer (handle))
return;
buffer = _cogl_vertex_buffer_pointer_from_handle (handle);
/* The objective now is to copy the attribute data supplied by the client
* into buffer objects, but it's important to minimize the number of
* redundant data uploads.
*
* We obviously aim to group together the attributes that are interleved so
* that they can be delivered in one go to the driver.
* All BOs for interleved data are created as STATIC_DRAW_ARB.
*
* Non interleved attributes tagged as INFREQUENT_RESUBMIT will be grouped
* together back to back in a single BO created as STATIC_DRAW_ARB
*
* Non interleved attributes tagged as FREQUENT_RESUBMIT will be copied into
* individual buffer objects, and the BO itself created DYNAMIC_DRAW_ARB
*
* If we are modifying a previously submitted CoglVertexBuffer then we are
* carefull not to needlesly delete OpenGL buffer objects and replace with
* new ones, instead we upload new data to the existing buffers.
*/
/* NB: We must forget attribute->pointer after submitting since the user
* is free to re-use that memory for other purposes now. */
/* Pseudo code:
*
* Broadly speaking we start with a list of unsorted attributes, and filter
* those into 'new' and 're-use' CoglVertexBufferVBO (CBO) lists. We then
* take the list of new CBO structs and compare with the CBOs that have
* already been submitted to the GPU (but ignoring those we already know will
* be re-used) to determine what other CBOs can be re-used, due to being
* superseded, and what new GL VBOs need to be created.
*
* We have three kinds of CBOs:
* - Unstrided CBOs
* These contain a single tightly packed attribute
* These are currently the only ones ever marked as FREQUENT_SUBMIT
* - Strided CBOs
* These typically contain multiple interleved sets of attributes,
* though they can contain just one attribute with a stride
* - Multi Pack CBOs
* These contain multiple attributes tightly packed back to back)
*
* First create a new-CBOs entry "new-multipack-CBO"
* Tag "new-multipack-CBO" as MULTIPACK + INFREQUENT_RESUBMIT
* For each unsorted attrib:
* if already marked as submitted:
* iterate reuse-CBOs:
* if we find one that contains this attribute:
* free redundant unsorted attrib struct
* remove the UNUSED flag from the attrib found in the reuse-CBO
* continue to next unsorted attrib
* iterate submitted VBOs:
* if we find one that contains this attribute:
* free redundant unsorted attrib struct
* unlink the vbo and move it to the list of reuse-CBOs
* mark all attributes except the one just matched as UNUSED
* assert (found)
* continue to next unsorted attrib
* if strided:
* iterate the new, strided, CBOs, to see if the attribute is
* interleved with one of them, if found:
* add to the matched CBO
* else if not found:
* create a new-CBOs entry tagged STRIDED + INFREQUENT_RESUBMIT
* else if unstrided && tagged with FREQUENT_RESUBMIT:
* create a new-CBOs entry tagged UNSTRIDED + FREQUENT_RESUBMIT
* else
* add to the new-multipack-CBO
* free list of unsorted-attribs
*
* Next compare the new list of CBOs with the submitted set and try to
* minimize the memory bandwidth required to upload the attributes and the
* overhead of creating new GL-BOs.
*
* We deal with four sets of CBOs:
* - The "new" CBOs
* (as determined above during filtering)
* - The "re-use" CBOs
* (as determined above during filtering)
* - The "submitted" CBOs
* (I.e. ones currently submitted to the GPU)
* - The "final" CBOs
* (The result of resolving the differences between the above sets)
*
* The re-use CBOs are dealt with first, and we simply delete any remaining
* attributes in these that are still marked as UNUSED, and move them
* to the list of final CBOs.
*
* Next we iterate through the "new" CBOs, searching for conflicts
* with the "submitted" CBOs and commit our decision to the "final" CBOs
*
* When searching for submitted entries we always unlink items from the
* submitted list once we make matches (before we make descisions
* based on the matches). If the CBO node is superseded it is freed,
* if it is modified but may be needed for more descisions later it is
* relinked back into the submitted list and if it's identical to a new
* CBO it will be linked into the final list.
*
* At the end the list of submitted CBOs represents the attributes that were
* deleted from the buffer.
*
* Iterate re-use-CBOs:
* Iterate attribs for each:
* if attrib UNUSED:
* remove the attrib from the CBO + free
* |Note: we could potentially mark this as a re-useable gap
* |if needs be later.
* add re-use CBO to the final-CBOs
* Iterate new-CBOs:
* List submitted CBOs conflicting with the this CBO (Unlinked items)
* found-target-BO=FALSE
* Iterate conflicting CBOs:
* Disassociate conflicting attribs from conflicting CBO struct
* If no attribs remain:
* If found-target-BO!=TRUE
* _AND_ If the total size of the conflicting CBO is compatible:
* |Note: We don't currently consider re-using oversized buffers
* found-target-BO=TRUE
* upload replacement data
* free submitted CBO struct
* add new CBO struct to final-CBOs
* else:
* delete conflict GL-BO
* delete conflict CBO struct
* else:
* relink CBO back into submitted-CBOs
*
* if found-target-BO == FALSE:
* create a new GL-BO
* upload data
* add new CBO struct to final-BOs
*
* Iterate through the remaining "submitted" CBOs:
* delete the submitted GL-BO
* free the submitted CBO struct
*/
new_multipack_vbo = g_slice_alloc (sizeof (CoglVertexBufferVBO));
new_multipack_vbo->vbo_name = 0;
new_multipack_vbo->flags =
COGL_VERTEX_BUFFER_VBO_FLAG_MULTIPACK
| COGL_VERTEX_BUFFER_VBO_FLAG_INFREQUENT_RESUBMIT;
new_multipack_vbo->vbo_bytes = 0;
new_multipack_vbo->attributes = NULL;
new_vbos = g_list_prepend (new_vbos, new_multipack_vbo);
/* We save the link pointer here, just so we can do a fast removal later if
* no attributes get added to this vbo. */
new_multipack_vbo_link = new_vbos;
/* Start with a list of unsorted attributes, and filter those into
* potential new Cogl BO structs
*/
for (tmp = buffer->new_attributes; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferAttrib *attribute = tmp->data;
if (attribute->flags & COGL_VERTEX_BUFFER_ATTRIB_FLAG_SUBMITTED)
{
/* If the attribute is already marked as submitted, then we need
* to find the existing VBO that contains it so we dont delete it.
*
* NB: this also frees the attribute struct since it's implicitly
* redundant in this case.
*/
filter_already_submitted_attribute (attribute,
&reuse_vbos,
&buffer->submitted_vbos);
}
else if (attribute->stride)
{
/* look for a CoglVertexBufferVBO that the attribute is
* interleved with. If one can't be found then a new
* CoglVertexBufferVBO is allocated and added to the list of
* new_vbos: */
filter_strided_attribute (attribute, &new_vbos);
}
else if (attribute->flags &
COGL_VERTEX_BUFFER_ATTRIB_FLAG_FREQUENT_RESUBMIT)
{
CoglVertexBufferVBO *cogl_vbo =
g_slice_alloc (sizeof (CoglVertexBufferVBO));
/* attributes we expect will be frequently resubmitted are placed
* in their own VBO so that updates don't impact other attributes
*/
cogl_vbo->vbo_name = 0;
cogl_vbo->flags =
COGL_VERTEX_BUFFER_VBO_FLAG_UNSTRIDED
| COGL_VERTEX_BUFFER_VBO_FLAG_FREQUENT_RESUBMIT;
cogl_vbo->attributes = NULL;
cogl_vbo->attributes = g_list_prepend (cogl_vbo->attributes,
attribute);
cogl_vbo->vbo_bytes = attribute->span_bytes;
new_vbos = g_list_prepend (new_vbos, cogl_vbo);
}
else
{
gsize gl_type_size = get_gl_type_size (attribute->flags);
/* Infrequently updated attributes just get packed back to back
* in a single VBO: */
new_multipack_vbo->attributes =
g_list_prepend (new_multipack_vbo->attributes,
attribute);
/* Note: we have to ensure that each run of attributes is
* naturally aligned according to its data type, which may
* require some padding bytes: */
/* XXX: We also have to be sure that the attributes aren't
* reorderd before being uploaded because the alignment padding
* is based on the adjacent attribute.
*/
PAD_FOR_ALIGNMENT (new_multipack_vbo->vbo_bytes, gl_type_size);
new_multipack_vbo->vbo_bytes += attribute->span_bytes;
}
}
/* At this point all buffer->new_attributes have been filtered into
* CoglVertexBufferVBOs... */
g_list_free (buffer->new_attributes);
buffer->new_attributes = NULL;
/* If the multipack vbo wasn't needed: */
if (new_multipack_vbo->attributes == NULL)
{
new_vbos = g_list_delete_link (new_vbos, new_multipack_vbo_link);
g_slice_free (CoglVertexBufferVBO, new_multipack_vbo);
}
for (tmp = reuse_vbos; tmp != NULL; tmp = tmp->next)
remove_unused_attributes (tmp->data);
final_vbos = g_list_concat (final_vbos, reuse_vbos);
for (tmp = new_vbos; tmp != NULL; tmp = tmp->next)
cogl_vertex_buffer_vbo_resolve (buffer, tmp->data, &final_vbos);
/* Anything left corresponds to deleted attributes: */
for (tmp = buffer->submitted_vbos; tmp != NULL; tmp = tmp->next)
cogl_vertex_buffer_vbo_free (tmp->data, TRUE);
g_list_free (buffer->submitted_vbos);
buffer->submitted_vbos = final_vbos;
}
static GLenum
get_gl_type_from_attribute_flags (CoglVertexBufferAttribFlags flags)
{
CoglVertexBufferAttribFlags gl_type =
flags & COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_MASK;
switch (gl_type)
{
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_BYTE:
return GL_BYTE;
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_UNSIGNED_BYTE:
return GL_UNSIGNED_BYTE;
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_SHORT:
return GL_SHORT;
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_UNSIGNED_SHORT:
return GL_UNSIGNED_SHORT;
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_FLOAT:
return GL_FLOAT;
#if HAVE_COGL_GL
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_INT:
return GL_INT;
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_UNSIGNED_INT:
return GL_UNSIGNED_INT;
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_GL_TYPE_DOUBLE:
return GL_DOUBLE;
#endif
default:
g_warning ("Couldn't convert from attribute flags (0x%08x) "
"to gl type enum\n", flags);
return 0;
}
}
static void
enable_state_for_drawing_attributes_buffer (CoglVertexBuffer *buffer)
{
GList *tmp;
GLenum gl_type;
GLuint generic_index = 0;
gulong enable_flags = COGL_ENABLE_BLEND;
/* FIXME: I don't think it's appropriate to force enable
* GL_BLEND here. */
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
for (tmp = buffer->submitted_vbos; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferVBO *cogl_vbo = tmp->data;
GList *tmp2;
GE (glBindBuffer (GL_ARRAY_BUFFER, cogl_vbo->vbo_name));
for (tmp2 = cogl_vbo->attributes; tmp2 != NULL; tmp2 = tmp2->next)
{
CoglVertexBufferAttrib *attribute = tmp2->data;
CoglVertexBufferAttribFlags type =
attribute->flags & COGL_VERTEX_BUFFER_ATTRIB_FLAG_TYPE_MASK;
if (!(attribute->flags & COGL_VERTEX_BUFFER_ATTRIB_FLAG_ENABLED))
continue;
gl_type = get_gl_type_from_attribute_flags (attribute->flags);
switch (type)
{
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_COLOR_ARRAY:
/* FIXME: go through cogl cache to enable color array */
GE (glEnableClientState (GL_COLOR_ARRAY));
GE (glColorPointer (attribute->n_components,
gl_type,
attribute->stride,
(const GLvoid *)attribute->u.vbo_offset));
break;
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_NORMAL_ARRAY:
/* FIXME: go through cogl cache to enable normal array */
GE (glEnableClientState (GL_NORMAL_ARRAY));
GE (glNormalPointer (gl_type,
attribute->stride,
(const GLvoid *)attribute->u.vbo_offset));
break;
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_TEXTURE_COORD_ARRAY:
/* FIXME: set the active texture unit */
/* NB: Cogl currently manages unit 0 */
enable_flags |= (COGL_ENABLE_TEXCOORD_ARRAY
| COGL_ENABLE_TEXTURE_2D);
/* FIXME: I don't think it's appropriate to force enable
* GL_TEXTURE_2D here. */
/* GE (glEnableClientState (GL_VERTEX_ARRAY)); */
GE (glTexCoordPointer (attribute->n_components,
gl_type,
attribute->stride,
(const GLvoid *)attribute->u.vbo_offset));
break;
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_VERTEX_ARRAY:
enable_flags |= COGL_ENABLE_VERTEX_ARRAY;
/* GE (glEnableClientState (GL_VERTEX_ARRAY)); */
GE (glVertexPointer (attribute->n_components,
gl_type,
attribute->stride,
(const GLvoid *)attribute->u.vbo_offset));
break;
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_CUSTOM_ARRAY:
{
#ifdef MAY_HAVE_PROGRAMABLE_GL
GLboolean normalized = GL_FALSE;
if (attribute->flags &
COGL_VERTEX_BUFFER_ATTRIB_FLAG_NORMALIZED)
normalized = GL_TRUE;
/* FIXME: go through cogl cache to enable generic array */
GE (glEnableVertexAttribArray (generic_index++));
GE (glVertexAttribPointer (generic_index,
attribute->n_components,
gl_type,
normalized,
attribute->stride,
(const GLvoid *)
attribute->u.vbo_offset));
#endif
}
break;
default:
g_warning ("Unrecognised attribute type 0x%08x", type);
}
}
}
cogl_enable (enable_flags);
}
static void
disable_state_for_drawing_buffer (CoglVertexBuffer *buffer)
{
GList *tmp;
GLenum gl_type;
GLuint generic_index = 0;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
/* Disable all the client state that cogl doesn't currently know
* about:
*/
GE (glBindBuffer (GL_ARRAY_BUFFER, 0));
generic_index = 0;
for (tmp = buffer->submitted_vbos; tmp != NULL; tmp = tmp->next)
{
CoglVertexBufferVBO *cogl_vbo = tmp->data;
GList *tmp2;
for (tmp2 = cogl_vbo->attributes; tmp2 != NULL; tmp2 = tmp2->next)
{
CoglVertexBufferAttrib *attribute = tmp2->data;
CoglVertexBufferAttribFlags type =
attribute->flags & COGL_VERTEX_BUFFER_ATTRIB_FLAG_TYPE_MASK;
if (!(attribute->flags & COGL_VERTEX_BUFFER_ATTRIB_FLAG_ENABLED))
continue;
gl_type = get_gl_type_from_attribute_flags(attribute->flags);
switch (type)
{
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_COLOR_ARRAY:
/* FIXME: go through cogl cache to enable color array */
GE (glDisableClientState (GL_COLOR_ARRAY));
break;
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_NORMAL_ARRAY:
/* FIXME: go through cogl cache to enable normal array */
GE (glDisableClientState (GL_NORMAL_ARRAY));
break;
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_TEXTURE_COORD_ARRAY:
/* FIXME: set the active texture unit */
/* NB: Cogl currently manages unit 0 */
/* GE (glDisableClientState (GL_VERTEX_ARRAY)); */
break;
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_VERTEX_ARRAY:
/* GE (glDisableClientState (GL_VERTEX_ARRAY)); */
break;
case COGL_VERTEX_BUFFER_ATTRIB_FLAG_CUSTOM_ARRAY:
#ifdef MAY_HAVE_PROGRAMABLE_GL
/* FIXME: go through cogl cache to enable generic array */
GE (glDisableVertexAttribArray (generic_index++));
#endif
break;
default:
g_warning ("Unrecognised attribute type 0x%08x", type);
}
}
}
}
void
cogl_vertex_buffer_draw (CoglHandle handle,
GLenum mode,
GLint first,
GLsizei count)
{
CoglVertexBuffer *buffer;
if (!cogl_is_vertex_buffer (handle))
return;
buffer = _cogl_vertex_buffer_pointer_from_handle (handle);
enable_state_for_drawing_attributes_buffer (buffer);
/* FIXME: flush cogl cache */
GE (glDrawArrays (mode, first, count));
disable_state_for_drawing_buffer (buffer);
}
void
cogl_vertex_buffer_draw_elements (CoglHandle handle,
GLenum mode,
GLuint min_index,
GLuint max_index,
GLsizei count,
GLenum indices_type,
const GLvoid *indices)
{
CoglVertexBuffer *buffer;
_COGL_GET_CONTEXT (ctx, NO_RETVAL);
if (!cogl_is_vertex_buffer (handle))
return;
buffer = _cogl_vertex_buffer_pointer_from_handle (handle);
enable_state_for_drawing_attributes_buffer (buffer);
/* FIXME: flush cogl cache */
GE (glDrawRangeElements (mode, min_index, max_index,
count, indices_type, indices));
disable_state_for_drawing_buffer (buffer);
}
static void
_cogl_vertex_buffer_free (CoglVertexBuffer *buffer)
{
GList *tmp;
for (tmp = buffer->submitted_vbos; tmp != NULL; tmp = tmp->next)
cogl_vertex_buffer_vbo_free (tmp->data, TRUE);
for (tmp = buffer->new_attributes; tmp != NULL; tmp = tmp->next)
cogl_vertex_buffer_attribute_free (tmp->data);
g_slice_free (CoglVertexBuffer, buffer);
}