0,0 → 1,191 |
/************************************************************************** |
* |
* Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas. |
* 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, sub license, 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 (including the |
* next paragraph) 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 NON-INFRINGEMENT. |
* IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS 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 "util/u_math.h" |
#include "util/u_memory.h" |
#include "pipe/p_defines.h" |
#include "pipe/p_shader_tokens.h" |
#include "draw_vs.h" |
#include "draw_pipe.h" |
|
struct twoside_stage { |
struct draw_stage stage; |
float sign; /**< +1 or -1 */ |
int attrib_front0, attrib_back0; |
int attrib_front1, attrib_back1; |
}; |
|
|
static INLINE struct twoside_stage *twoside_stage( struct draw_stage *stage ) |
{ |
return (struct twoside_stage *)stage; |
} |
|
/** |
* Copy back color(s) to front color(s). |
*/ |
static INLINE struct vertex_header * |
copy_bfc( struct twoside_stage *twoside, |
const struct vertex_header *v, |
unsigned idx ) |
{ |
struct vertex_header *tmp = dup_vert( &twoside->stage, v, idx ); |
|
if (twoside->attrib_back0 >= 0 && twoside->attrib_front0 >= 0) { |
COPY_4FV(tmp->data[twoside->attrib_front0], |
tmp->data[twoside->attrib_back0]); |
} |
if (twoside->attrib_back1 >= 0 && twoside->attrib_front1 >= 0) { |
COPY_4FV(tmp->data[twoside->attrib_front1], |
tmp->data[twoside->attrib_back1]); |
} |
|
return tmp; |
} |
|
|
/* Twoside tri: |
*/ |
static void twoside_tri( struct draw_stage *stage, |
struct prim_header *header ) |
{ |
struct twoside_stage *twoside = twoside_stage(stage); |
|
if (header->det * twoside->sign < 0.0) { |
/* this is a back-facing triangle */ |
struct prim_header tmp; |
|
tmp.det = header->det; |
tmp.flags = header->flags; |
tmp.pad = header->pad; |
/* copy back attribs to front attribs */ |
tmp.v[0] = copy_bfc(twoside, header->v[0], 0); |
tmp.v[1] = copy_bfc(twoside, header->v[1], 1); |
tmp.v[2] = copy_bfc(twoside, header->v[2], 2); |
|
stage->next->tri( stage->next, &tmp ); |
} |
else { |
stage->next->tri( stage->next, header ); |
} |
} |
|
|
|
static void twoside_first_tri( struct draw_stage *stage, |
struct prim_header *header ) |
{ |
struct twoside_stage *twoside = twoside_stage(stage); |
const struct draw_vertex_shader *vs = stage->draw->vs.vertex_shader; |
uint i; |
|
twoside->attrib_front0 = -1; |
twoside->attrib_front1 = -1; |
twoside->attrib_back0 = -1; |
twoside->attrib_back1 = -1; |
|
/* Find which vertex shader outputs are front/back colors */ |
for (i = 0; i < vs->info.num_outputs; i++) { |
if (vs->info.output_semantic_name[i] == TGSI_SEMANTIC_COLOR) { |
if (vs->info.output_semantic_index[i] == 0) |
twoside->attrib_front0 = i; |
else |
twoside->attrib_front1 = i; |
} |
if (vs->info.output_semantic_name[i] == TGSI_SEMANTIC_BCOLOR) { |
if (vs->info.output_semantic_index[i] == 0) |
twoside->attrib_back0 = i; |
else |
twoside->attrib_back1 = i; |
} |
} |
|
/* |
* We'll multiply the primitive's determinant by this sign to determine |
* if the triangle is back-facing (negative). |
* sign = -1 for CCW, +1 for CW |
*/ |
twoside->sign = stage->draw->rasterizer->front_ccw ? -1.0f : 1.0f; |
|
stage->tri = twoside_tri; |
stage->tri( stage, header ); |
} |
|
|
static void twoside_flush( struct draw_stage *stage, unsigned flags ) |
{ |
stage->tri = twoside_first_tri; |
stage->next->flush( stage->next, flags ); |
} |
|
|
static void twoside_reset_stipple_counter( struct draw_stage *stage ) |
{ |
stage->next->reset_stipple_counter( stage->next ); |
} |
|
|
static void twoside_destroy( struct draw_stage *stage ) |
{ |
draw_free_temp_verts( stage ); |
FREE( stage ); |
} |
|
|
/** |
* Create twoside pipeline stage. |
*/ |
struct draw_stage *draw_twoside_stage( struct draw_context *draw ) |
{ |
struct twoside_stage *twoside = CALLOC_STRUCT(twoside_stage); |
if (twoside == NULL) |
goto fail; |
|
twoside->stage.draw = draw; |
twoside->stage.name = "twoside"; |
twoside->stage.next = NULL; |
twoside->stage.point = draw_pipe_passthrough_point; |
twoside->stage.line = draw_pipe_passthrough_line; |
twoside->stage.tri = twoside_first_tri; |
twoside->stage.flush = twoside_flush; |
twoside->stage.reset_stipple_counter = twoside_reset_stipple_counter; |
twoside->stage.destroy = twoside_destroy; |
|
if (!draw_alloc_temp_verts( &twoside->stage, 3 )) |
goto fail; |
|
return &twoside->stage; |
|
fail: |
if (twoside) |
twoside->stage.destroy( &twoside->stage ); |
|
return NULL; |
} |