/**************************************************************************
*
* Copyright 2007 VMware, Inc.
* 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 VMWARE 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 <keithw@vmware.com>
*/
#include "util/u_math.h"
#include "util/u_memory.h"
#include "pipe/p_shader_tokens.h"
#include "draw_vs.h"
#include "draw_fs.h"
#include "draw_pipe.h"
/** subclass of draw_stage */
struct flat_stage
{
struct draw_stage stage;
uint num_flat_attribs;
uint flat_attribs[PIPE_MAX_SHADER_OUTPUTS]; /* flatshaded attribs */
};
static INLINE struct flat_stage *
flat_stage(struct draw_stage *stage)
{
return (struct flat_stage *) stage;
}
/** Copy all the constant attributes from 'src' vertex to 'dst' vertex */
static INLINE void copy_flats( struct draw_stage *stage,
struct vertex_header *dst,
const struct vertex_header *src )
{
const struct flat_stage *flat = flat_stage(stage);
uint i;
for (i = 0; i < flat->num_flat_attribs; i++) {
const uint attr = flat->flat_attribs[i];
COPY_4FV(dst->data[attr], src->data[attr]);
}
}
/** Copy all the color attributes from src vertex to dst0 & dst1 vertices */
static INLINE void copy_flats2( struct draw_stage *stage,
struct vertex_header *dst0,
struct vertex_header *dst1,
const struct vertex_header *src )
{
const struct flat_stage *flat = flat_stage(stage);
uint i;
for (i = 0; i < flat->num_flat_attribs; i++) {
const uint attr = flat->flat_attribs[i];
COPY_4FV(dst0->data[attr], src->data[attr]);
COPY_4FV(dst1->data[attr], src->data[attr]);
}
}
/**
* Flatshade tri. Not required for clipping which handles this on its own,
* but required for unfilled tris and other primitive-changing stages
* (like widelines). If no such stages are active, handled by hardware.
*/
static void flatshade_tri_0( struct draw_stage *stage,
struct prim_header *header )
{
struct prim_header tmp;
tmp.det = header->det;
tmp.flags = header->flags;
tmp.pad = header->pad;
tmp.v[0] = header->v[0];
tmp.v[1] = dup_vert(stage, header->v[1], 0);
tmp.v[2] = dup_vert(stage, header->v[2], 1);
copy_flats2(stage, tmp.v[1], tmp.v[2], tmp.v[0]);
stage->next->tri( stage->next, &tmp );
}
static void flatshade_tri_2( struct draw_stage *stage,
struct prim_header *header )
{
struct prim_header tmp;
tmp.det = header->det;
tmp.flags = header->flags;
tmp.pad = header->pad;
tmp.v[0] = dup_vert(stage, header->v[0], 0);
tmp.v[1] = dup_vert(stage, header->v[1], 1);
tmp.v[2] = header->v[2];
copy_flats2(stage, tmp.v[0], tmp.v[1], tmp.v[2]);
stage->next->tri( stage->next, &tmp );
}
/**
* Flatshade line.
*/
static void flatshade_line_0( struct draw_stage *stage,
struct prim_header *header )
{
struct prim_header tmp;
tmp.det = header->det;
tmp.flags = header->flags;
tmp.pad = header->pad;
tmp.v[0] = header->v[0];
tmp.v[1] = dup_vert(stage, header->v[1], 0);
copy_flats(stage, tmp.v[1], tmp.v[0]);
stage->next->line( stage->next, &tmp );
}
static void flatshade_line_1( struct draw_stage *stage,
struct prim_header *header )
{
struct prim_header tmp;
tmp.det = header->det;
tmp.flags = header->flags;
tmp.pad = header->pad;
tmp.v[0] = dup_vert(stage, header->v[0], 0);
tmp.v[1] = header->v[1];
copy_flats(stage, tmp.v[0], tmp.v[1]);
stage->next->line( stage->next, &tmp );
}
static int
find_interp(const struct draw_fragment_shader *fs, int *indexed_interp,
uint semantic_name, uint semantic_index)
{
int interp;
/* If it's gl_{Front,Back}{,Secondary}Color, pick up the mode
* from the array we've filled before. */
if (semantic_name == TGSI_SEMANTIC_COLOR ||
semantic_name == TGSI_SEMANTIC_BCOLOR) {
interp = indexed_interp[semantic_index];
} else {
/* Otherwise, search in the FS inputs, with a decent default
* if we don't find it.
*/
uint j;
interp = TGSI_INTERPOLATE_PERSPECTIVE;
if (fs) {
for (j = 0; j < fs->info.num_inputs; j++) {
if (semantic_name == fs->info.input_semantic_name[j] &&
semantic_index == fs->info.input_semantic_index[j]) {
interp = fs->info.input_interpolate[j];
break;
}
}
}
}
return interp;
}
static void flatshade_init_state( struct draw_stage *stage )
{
struct flat_stage *flat = flat_stage(stage);
const struct draw_context *draw = stage->draw;
const struct draw_fragment_shader *fs = draw->fs.fragment_shader;
const struct tgsi_shader_info *info = draw_get_shader_info(draw);
uint i, j;
/* Find which vertex shader outputs need constant interpolation, make a list */
/* XXX: this code is a near exact copy of the one in clip_init_state.
* The latter also cares about perspective though.
*/
/* First pick up the interpolation mode for
* gl_Color/gl_SecondaryColor, with the correct default.
*/
int indexed_interp[2];
indexed_interp[0] = indexed_interp[1] = draw->rasterizer->flatshade ?
TGSI_INTERPOLATE_CONSTANT : TGSI_INTERPOLATE_PERSPECTIVE;
if (fs) {
for (i = 0; i < fs->info.num_inputs; i++) {
if (fs->info.input_semantic_name[i] == TGSI_SEMANTIC_COLOR) {
if (fs->info.input_interpolate[i] != TGSI_INTERPOLATE_COLOR)
indexed_interp[fs->info.input_semantic_index[i]] = fs->info.input_interpolate[i];
}
}
}
/* Then resolve the interpolation mode for every output attribute.
*
* Given how the rest of the code, the most efficient way is to
* have a vector of flat-mode attributes.
*/
flat->num_flat_attribs = 0;
for (i = 0; i < info->num_outputs; i++) {
/* Find the interpolation mode for a specific attribute */
int interp = find_interp(fs, indexed_interp,
info->output_semantic_name[i],
info->output_semantic_index[i]);
/* If it's flat, add it to the flat vector. */
if (interp == TGSI_INTERPOLATE_CONSTANT) {
flat->flat_attribs[flat->num_flat_attribs] = i;
flat->num_flat_attribs++;
}
}
/* Search the extra vertex attributes */
for (j = 0; j < draw->extra_shader_outputs.num; j++) {
/* Find the interpolation mode for a specific attribute */
int interp = find_interp(fs, indexed_interp,
draw->extra_shader_outputs.semantic_name[j],
draw->extra_shader_outputs.semantic_index[j]);
/* If it's flat, add it to the flat vector. */
if (interp == TGSI_INTERPOLATE_CONSTANT) {
flat->flat_attribs[flat->num_flat_attribs] = i + j;
flat->num_flat_attribs++;
}
}
/* Choose flatshade routine according to provoking vertex:
*/
if (draw->rasterizer->flatshade_first) {
stage->line = flatshade_line_0;
stage->tri = flatshade_tri_0;
}
else {
stage->line = flatshade_line_1;
stage->tri = flatshade_tri_2;
}
}
static void flatshade_first_tri( struct draw_stage *stage,
struct prim_header *header )
{
flatshade_init_state( stage );
stage->tri( stage, header );
}
static void flatshade_first_line( struct draw_stage *stage,
struct prim_header *header )
{
flatshade_init_state( stage );
stage->line( stage, header );
}
static void flatshade_flush( struct draw_stage *stage,
unsigned flags )
{
stage->tri = flatshade_first_tri;
stage->line = flatshade_first_line;
stage->next->flush( stage->next, flags );
}
static void flatshade_reset_stipple_counter( struct draw_stage *stage )
{
stage->next->reset_stipple_counter( stage->next );
}
static void flatshade_destroy( struct draw_stage *stage )
{
draw_free_temp_verts( stage );
FREE( stage );
}
/**
* Create flatshading drawing stage.
*/
struct draw_stage *draw_flatshade_stage( struct draw_context *draw )
{
struct flat_stage *flatshade = CALLOC_STRUCT(flat_stage);
if (flatshade == NULL)
goto fail;
flatshade->stage.draw = draw;
flatshade->stage.name = "flatshade";
flatshade->stage.next = NULL;
flatshade->stage.point = draw_pipe_passthrough_point;
flatshade->stage.line = flatshade_first_line;
flatshade->stage.tri = flatshade_first_tri;
flatshade->stage.flush = flatshade_flush;
flatshade->stage.reset_stipple_counter = flatshade_reset_stipple_counter;
flatshade->stage.destroy = flatshade_destroy;
if (!draw_alloc_temp_verts( &flatshade->stage, 2 ))
goto fail;
return &flatshade->stage;
fail:
if (flatshade)
flatshade->stage.destroy( &flatshade->stage );
return NULL;
}