/*
* Mesa 3-D graphics library
*
* Copyright (C) 1999-2006 Brian Paul All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Authors:
* Keith Whitwell <keith@tungstengraphics.com>
*/
/* Helper for drivers which find themselves rendering a range of
* indices starting somewhere above zero. Typically the application
* is issuing multiple DrawArrays() or DrawElements() to draw
* successive primitives layed out linearly in the vertex arrays.
* Unless the vertex arrays are all in a VBO, the OpenGL semantics
* imply that we need to re-upload the vertex data on each draw call.
* In that case, we want to avoid starting the upload at zero, as it
* will mean every draw call uploads an increasing amount of not-used
* vertex data. Worse - in the software tnl module, all those
* vertices will be transformed and lit.
*
* If we just upload the new data, however, the indices will be
* incorrect as we tend to upload each set of vertex data to a new
* region.
*
* This file provides a helper to adjust the arrays, primitives and
* indices of a draw call so that it can be re-issued with a min_index
* of zero.
*/
#include "main/glheader.h"
#include "main/imports.h"
#include "main/mtypes.h"
#include "vbo.h"
#define REBASE(TYPE) \
static void *rebase_##TYPE( const void *ptr, \
GLuint count, \
TYPE min_index ) \
{ \
const TYPE *in = (TYPE *)ptr; \
TYPE *tmp_indices = malloc(count * sizeof(TYPE)); \
GLuint i; \
\
for (i = 0; i < count; i++) \
tmp_indices[i] = in[i] - min_index; \
\
return (void *)tmp_indices; \
}
REBASE(GLuint)
REBASE(GLushort)
REBASE(GLubyte)
GLboolean vbo_all_varyings_in_vbos( const struct gl_client_array *arrays[] )
{
GLuint i;
for (i = 0; i < VERT_ATTRIB_MAX; i++)
if (arrays[i]->StrideB &&
arrays[i]->BufferObj->Name == 0)
return GL_FALSE;
return GL_TRUE;
}
GLboolean vbo_any_varyings_in_vbos( const struct gl_client_array *arrays[] )
{
GLuint i;
for (i = 0; i < VERT_ATTRIB_MAX; i++)
if (arrays[i]->BufferObj->Name != 0)
return GL_TRUE;
return GL_FALSE;
}
/* Adjust primitives, indices and vertex definitions so that min_index
* becomes zero. There are lots of reasons for wanting to do this, eg:
*
* Software tnl:
* - any time min_index != 0, otherwise unused vertices lower than
* min_index will be transformed.
*
* Hardware tnl:
* - if ib != NULL and min_index != 0, otherwise vertices lower than
* min_index will be uploaded. Requires adjusting index values.
*
* - if ib == NULL and min_index != 0, just for convenience so this doesn't
* have to be handled within the driver.
*
* Hardware tnl with VBO support:
* - as above, but only when vertices are not (all?) in VBO's.
* - can't save time by trying to upload half a vbo - typically it is
* all or nothing.
*/
void vbo_rebase_prims( struct gl_context *ctx,
const struct gl_client_array *arrays[],
const struct _mesa_prim *prim,
GLuint nr_prims,
const struct _mesa_index_buffer *ib,
GLuint min_index,
GLuint max_index,
vbo_draw_func draw )
{
struct gl_client_array tmp_arrays[VERT_ATTRIB_MAX];
const struct gl_client_array *tmp_array_pointers[VERT_ATTRIB_MAX];
struct _mesa_index_buffer tmp_ib;
struct _mesa_prim *tmp_prims = NULL;
const struct gl_client_array **saved_arrays = ctx->Array._DrawArrays;
void *tmp_indices = NULL;
GLuint i;
if (0)
printf("%s %d..%d\n", __FUNCTION__
, min_index
, max_index
);
/* XXX this path is disabled for now.
* There's rendering corruption in some apps when it's enabled.
*/
if (0 && ib && ctx->Extensions.ARB_draw_elements_base_vertex) {
/* If we can just tell the hardware or the TNL to interpret our
* indices with a different base, do so.
*/
tmp_prims
= malloc(sizeof(*prim
) * nr_prims
);
for (i = 0; i < nr_prims; i++) {
tmp_prims[i] = prim[i];
tmp_prims[i].basevertex -= min_index;
}
prim = tmp_prims;
} else if (ib) {
/* Unfortunately need to adjust each index individually.
*/
GLboolean map_ib = ib->obj->Name && !ib->obj->Pointer;
void *ptr;
if (map_ib)
ctx->Driver.MapBufferRange(ctx, 0, ib->obj->Size, GL_MAP_READ_BIT,
ib->obj);
ptr = ADD_POINTERS(ib->obj->Pointer, ib->ptr);
/* Some users might prefer it if we translated elements to
* GLuints here. Others wouldn't...
*/
switch (ib->type) {
case GL_UNSIGNED_INT:
tmp_indices = rebase_GLuint( ptr, ib->count, min_index );
break;
case GL_UNSIGNED_SHORT:
tmp_indices = rebase_GLushort( ptr, ib->count, min_index );
break;
case GL_UNSIGNED_BYTE:
tmp_indices = rebase_GLubyte( ptr, ib->count, min_index );
break;
}
if (map_ib)
ctx->Driver.UnmapBuffer(ctx, ib->obj);
tmp_ib.obj = ctx->Shared->NullBufferObj;
tmp_ib.ptr = tmp_indices;
tmp_ib.count = ib->count;
tmp_ib.type = ib->type;
ib = &tmp_ib;
}
else {
/* Otherwise the primitives need adjustment.
*/
tmp_prims
= malloc(sizeof(*prim
) * nr_prims
);
for (i = 0; i < nr_prims; i++) {
/* If this fails, it could indicate an application error:
*/
assert(prim
[i
].
start >= min_index
);
tmp_prims[i] = prim[i];
tmp_prims[i].start -= min_index;
}
prim = tmp_prims;
}
/* Just need to adjust the pointer values on each incoming array.
* This works for VBO and non-vbo rendering and shouldn't pesimize
* VBO-based upload schemes. However this may still not be a fast
* path for hardware tnl for VBO based rendering as most machines
* will be happier if you just specify a starting vertex value in
* each primitive.
*
* For drivers with hardware tnl, you only want to do this if you
* are forced to, eg non-VBO indexed rendering with start != 0.
*/
for (i = 0; i < VERT_ATTRIB_MAX; i++) {
tmp_arrays[i] = *arrays[i];
tmp_arrays[i].Ptr += min_index * tmp_arrays[i].StrideB;
tmp_array_pointers[i] = &tmp_arrays[i];
}
/* Re-issue the draw call.
*/
ctx->Array._DrawArrays = tmp_array_pointers;
ctx->NewDriverState |= ctx->DriverFlags.NewArray;
draw( ctx,
prim,
nr_prims,
ib,
GL_TRUE,
0,
max_index - min_index,
NULL );
ctx->Array._DrawArrays = saved_arrays;
ctx->NewDriverState |= ctx->DriverFlags.NewArray;
}