/*
* Mesa 3-D graphics library
* Version: 6.5
*
* 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
* BRIAN PAUL 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>
*/
#include "main/glheader.h"
#include "main/colormac.h"
#include "main/macros.h"
#include "main/imports.h"
#include "main/mtypes.h"
#include "math/m_xform.h"
#include "t_context.h"
#include "t_pipeline.h"
struct vertex_stage_data {
GLvector4f eye;
GLvector4f clip;
GLvector4f proj;
GLubyte *clipmask;
GLubyte ormask;
GLubyte andmask;
};
#define VERTEX_STAGE_DATA(stage) ((struct vertex_stage_data *)stage->privatePtr)
/* This function implements cliptesting for user-defined clip planes.
* The clipping of primitives to these planes is implemented in
* t_render_clip.h.
*/
#define USER_CLIPTEST(NAME, SZ) \
static void NAME( struct gl_context *ctx, \
GLvector4f *clip, \
GLubyte *clipmask, \
GLubyte *clipormask, \
GLubyte *clipandmask ) \
{ \
GLuint p; \
\
for (p = 0; p < ctx->Const.MaxClipPlanes; p++) \
if (ctx->Transform.ClipPlanesEnabled & (1 << p)) { \
GLuint nr, i; \
const GLfloat a = ctx->Transform._ClipUserPlane[p][0]; \
const GLfloat b = ctx->Transform._ClipUserPlane[p][1]; \
const GLfloat c = ctx->Transform._ClipUserPlane[p][2]; \
const GLfloat d = ctx->Transform._ClipUserPlane[p][3]; \
GLfloat *coord = (GLfloat *)clip->data; \
GLuint stride = clip->stride; \
GLuint count = clip->count; \
\
for (nr = 0, i = 0 ; i < count ; i++) { \
GLfloat dp = coord[0] * a + coord[1] * b; \
if (SZ > 2) dp += coord[2] * c; \
if (SZ > 3) dp += coord[3] * d; else dp += d; \
\
if (dp < 0) { \
nr++; \
clipmask[i] |= CLIP_USER_BIT; \
} \
\
STRIDE_F(coord, stride); \
} \
\
if (nr > 0) { \
*clipormask |= CLIP_USER_BIT; \
if (nr == count) { \
*clipandmask |= CLIP_USER_BIT; \
return; \
} \
} \
} \
}
USER_CLIPTEST(userclip2, 2)
USER_CLIPTEST(userclip3, 3)
USER_CLIPTEST(userclip4, 4)
static void (*(usercliptab[5]))( struct gl_context *,
GLvector4f *, GLubyte *,
GLubyte *, GLubyte * ) =
{
NULL,
NULL,
userclip2,
userclip3,
userclip4
};
void
tnl_clip_prepare(struct gl_context *ctx)
{
/* Neither the x86 nor sparc asm cliptest functions have been updated
* for ARB_depth_clamp, so force the C paths.
*/
if (ctx->Transform.DepthClamp) {
static GLboolean c_funcs_installed = GL_FALSE;
if (!c_funcs_installed) {
init_c_cliptest();
c_funcs_installed = GL_TRUE;
}
}
}
static GLboolean run_vertex_stage( struct gl_context *ctx,
struct tnl_pipeline_stage *stage )
{
struct vertex_stage_data *store = (struct vertex_stage_data *)stage->privatePtr;
TNLcontext *tnl = TNL_CONTEXT(ctx);
struct vertex_buffer *VB = &tnl->vb;
if (ctx->VertexProgram._Current)
return GL_TRUE;
tnl_clip_prepare(ctx);
if (ctx->_NeedEyeCoords) {
/* Separate modelview transformation:
* Use combined ModelProject to avoid some depth artifacts
*/
if (ctx->ModelviewMatrixStack.Top->type == MATRIX_IDENTITY)
VB->EyePtr = VB->AttribPtr[_TNL_ATTRIB_POS];
else
VB->EyePtr = TransformRaw( &store->eye,
ctx->ModelviewMatrixStack.Top,
VB->AttribPtr[_TNL_ATTRIB_POS]);
}
VB->ClipPtr = TransformRaw( &store->clip,
&ctx->_ModelProjectMatrix,
VB->AttribPtr[_TNL_ATTRIB_POS] );
/* Drivers expect this to be clean to element 4...
*/
switch (VB->ClipPtr->size) {
case 1:
/* impossible */
case 2:
_mesa_vector4f_clean_elem( VB->ClipPtr, VB->Count, 2 );
/* fall-through */
case 3:
_mesa_vector4f_clean_elem( VB->ClipPtr, VB->Count, 3 );
/* fall-through */
case 4:
break;
}
/* Cliptest and perspective divide. Clip functions must clear
* the clipmask.
*/
store->ormask = 0;
store->andmask = CLIP_FRUSTUM_BITS;
if (tnl->NeedNdcCoords) {
VB->NdcPtr =
_mesa_clip_tab[VB->ClipPtr->size]( VB->ClipPtr,
&store->proj,
store->clipmask,
&store->ormask,
&store->andmask,
!ctx->Transform.DepthClamp );
}
else {
VB->NdcPtr = NULL;
_mesa_clip_np_tab[VB->ClipPtr->size]( VB->ClipPtr,
NULL,
store->clipmask,
&store->ormask,
&store->andmask,
!ctx->Transform.DepthClamp );
}
if (store->andmask)
return GL_FALSE;
/* Test userclip planes. This contributes to VB->ClipMask, so
* is essentially required to be in this stage.
*/
if (ctx->Transform.ClipPlanesEnabled) {
usercliptab[VB->ClipPtr->size]( ctx,
VB->ClipPtr,
store->clipmask,
&store->ormask,
&store->andmask );
if (store->andmask)
return GL_FALSE;
}
VB->ClipAndMask = store->andmask;
VB->ClipOrMask = store->ormask;
VB->ClipMask = store->clipmask;
return GL_TRUE;
}
static GLboolean init_vertex_stage( struct gl_context *ctx,
struct tnl_pipeline_stage *stage )
{
struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
struct vertex_stage_data *store;
GLuint size = VB->Size;
stage->privatePtr = CALLOC(sizeof(*store));
store = VERTEX_STAGE_DATA(stage);
if (!store)
return GL_FALSE;
_mesa_vector4f_alloc( &store->eye, 0, size, 32 );
_mesa_vector4f_alloc( &store->clip, 0, size, 32 );
_mesa_vector4f_alloc( &store->proj, 0, size, 32 );
store->clipmask = (GLubyte *) _mesa_align_malloc(sizeof(GLubyte)*size, 32 );
if (!store->clipmask ||
!store->eye.data ||
!store->clip.data ||
!store->proj.data)
return GL_FALSE;
return GL_TRUE;
}
static void dtr( struct tnl_pipeline_stage *stage )
{
struct vertex_stage_data *store = VERTEX_STAGE_DATA(stage);
if (store) {
_mesa_vector4f_free( &store->eye );
_mesa_vector4f_free( &store->clip );
_mesa_vector4f_free( &store->proj );
_mesa_align_free( store->clipmask );
FREE(store);
stage->privatePtr = NULL;
stage->run = init_vertex_stage;
}
}
const struct tnl_pipeline_stage _tnl_vertex_transform_stage =
{
"modelview/project/cliptest/divide",
NULL, /* private data */
init_vertex_stage,
dtr, /* destructor */
NULL,
run_vertex_stage /* run -- initially set to init */
};