/**************************************************************************
*
* 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>
*/
/**
* Notes on wide points and sprite mode:
*
* In wide point/sprite mode we effectively need to convert each incoming
* vertex into four outgoing vertices specifying the corners of a quad.
* Since we don't (yet) have geometry shaders, we have to handle this here
* in the draw module.
*
* For sprites, it also means that this is where we have to handle texcoords
* for the vertices of the quad. OpenGL's GL_COORD_REPLACE state specifies
* if/how enabled texcoords are automatically generated for sprites. We pass
* that info through gallium in the pipe_rasterizer_state::sprite_coord_mode
* array.
*
* Additionally, GLSL's gl_PointCoord fragment attribute has to be handled
* here as well. This is basically an additional texture/generic attribute
* that varies .x from 0 to 1 horizontally across the point and varies .y
* vertically from 0 to 1 down the sprite.
*
* With geometry shaders, the state tracker could create a GS to do
* most/all of this.
*/
#include "pipe/p_screen.h"
#include "pipe/p_context.h"
#include "util/u_math.h"
#include "util/u_memory.h"
#include "pipe/p_defines.h"
#include "pipe/p_shader_tokens.h"
#include "draw_fs.h"
#include "draw_vs.h"
#include "draw_pipe.h"
struct widepoint_stage {
struct draw_stage stage; /**< base class */
float half_point_size;
float xbias;
float ybias;
/** for automatic texcoord generation/replacement */
uint num_texcoord_gen;
uint texcoord_gen_slot[PIPE_MAX_SHADER_OUTPUTS];
/* TGSI_SEMANTIC to which sprite_coord_enable applies */
unsigned sprite_coord_semantic;
int psize_slot;
};
static INLINE struct widepoint_stage *
widepoint_stage( struct draw_stage *stage )
{
return (struct widepoint_stage *)stage;
}
/**
* Set the vertex texcoords for sprite mode.
* Coords may be left untouched or set to a right-side-up or upside-down
* orientation.
*/
static void set_texcoords(const struct widepoint_stage *wide,
struct vertex_header *v, const float tc[4])
{
const struct draw_context *draw = wide->stage.draw;
const struct pipe_rasterizer_state *rast = draw->rasterizer;
const uint texcoord_mode = rast->sprite_coord_mode;
uint i;
for (i = 0; i < wide->num_texcoord_gen; i++) {
const uint slot = wide->texcoord_gen_slot[i];
v->data[slot][0] = tc[0];
if (texcoord_mode == PIPE_SPRITE_COORD_LOWER_LEFT)
v->data[slot][1] = 1.0f - tc[1];
else
v->data[slot][1] = tc[1];
v->data[slot][2] = tc[2];
v->data[slot][3] = tc[3];
}
}
/* If there are lots of sprite points (and why wouldn't there be?) it
* would probably be more sensible to change hardware setup to
* optimize this rather than doing the whole thing in software like
* this.
*/
static void widepoint_point( struct draw_stage *stage,
struct prim_header *header )
{
const struct widepoint_stage *wide = widepoint_stage(stage);
const unsigned pos = draw_current_shader_position_output(stage->draw);
const boolean sprite = (boolean) stage->draw->rasterizer->point_quad_rasterization;
float half_size;
float left_adj, right_adj, bot_adj, top_adj;
struct prim_header tri;
/* four dups of original vertex */
struct vertex_header *v0 = dup_vert(stage, header->v[0], 0);
struct vertex_header *v1 = dup_vert(stage, header->v[0], 1);
struct vertex_header *v2 = dup_vert(stage, header->v[0], 2);
struct vertex_header *v3 = dup_vert(stage, header->v[0], 3);
float *pos0 = v0->data[pos];
float *pos1 = v1->data[pos];
float *pos2 = v2->data[pos];
float *pos3 = v3->data[pos];
/* point size is either per-vertex or fixed size */
if (wide->psize_slot >= 0) {
half_size = header->v[0]->data[wide->psize_slot][0];
half_size *= 0.5f;
}
else {
half_size = wide->half_point_size;
}
left_adj = -half_size + wide->xbias;
right_adj = half_size + wide->xbias;
bot_adj = half_size + wide->ybias;
top_adj = -half_size + wide->ybias;
pos0[0] += left_adj;
pos0[1] += top_adj;
pos1[0] += left_adj;
pos1[1] += bot_adj;
pos2[0] += right_adj;
pos2[1] += top_adj;
pos3[0] += right_adj;
pos3[1] += bot_adj;
if (sprite) {
static const float tex00[4] = { 0, 0, 0, 1 };
static const float tex01[4] = { 0, 1, 0, 1 };
static const float tex11[4] = { 1, 1, 0, 1 };
static const float tex10[4] = { 1, 0, 0, 1 };
set_texcoords( wide, v0, tex00 );
set_texcoords( wide, v1, tex01 );
set_texcoords( wide, v2, tex10 );
set_texcoords( wide, v3, tex11 );
}
tri.det = header->det; /* only the sign matters */
tri.v[0] = v0;
tri.v[1] = v2;
tri.v[2] = v3;
stage->next->tri( stage->next, &tri );
tri.v[0] = v0;
tri.v[1] = v3;
tri.v[2] = v1;
stage->next->tri( stage->next, &tri );
}
static void
widepoint_first_point(struct draw_stage *stage,
struct prim_header *header)
{
struct widepoint_stage *wide = widepoint_stage(stage);
struct draw_context *draw = stage->draw;
struct pipe_context *pipe = draw->pipe;
const struct pipe_rasterizer_state *rast = draw->rasterizer;
void *r;
wide->half_point_size = 0.5f * rast->point_size;
wide->xbias = 0.0;
wide->ybias = 0.0;
if (rast->half_pixel_center) {
wide->xbias = 0.125;
wide->ybias = -0.125;
}
/* Disable triangle culling, stippling, unfilled mode etc. */
r = draw_get_rasterizer_no_cull(draw, rast->scissor, rast->flatshade);
draw->suspend_flushing = TRUE;
pipe->bind_rasterizer_state(pipe, r);
draw->suspend_flushing = FALSE;
/* XXX we won't know the real size if it's computed by the vertex shader! */
if ((rast->point_size > draw->pipeline.wide_point_threshold) ||
(rast->point_quad_rasterization && draw->pipeline.point_sprite)) {
stage->point = widepoint_point;
}
else {
stage->point = draw_pipe_passthrough_point;
}
draw_remove_extra_vertex_attribs(draw);
if (rast->point_quad_rasterization) {
const struct draw_fragment_shader *fs = draw->fs.fragment_shader;
uint i;
wide->num_texcoord_gen = 0;
/* Loop over fragment shader inputs looking for the PCOORD input or inputs
* for which bit 'k' in sprite_coord_enable is set.
*/
for (i = 0; i < fs->info.num_inputs; i++) {
int slot;
const unsigned sn = fs->info.input_semantic_name[i];
const unsigned si = fs->info.input_semantic_index[i];
if (sn == wide->sprite_coord_semantic) {
/* Note that sprite_coord_enable is a bitfield of 32 bits. */
if (si >= 32 || !(rast->sprite_coord_enable & (1 << si)))
continue;
} else if (sn != TGSI_SEMANTIC_PCOORD) {
continue;
}
/* OK, this generic attribute needs to be replaced with a
* sprite coord (see above).
*/
slot = draw_alloc_extra_vertex_attrib(draw, sn, si);
/* add this slot to the texcoord-gen list */
wide->texcoord_gen_slot[wide->num_texcoord_gen++] = slot;
}
}
wide->psize_slot = -1;
if (rast->point_size_per_vertex) {
/* find PSIZ vertex output */
const struct draw_vertex_shader *vs = draw->vs.vertex_shader;
uint i;
for (i = 0; i < vs->info.num_outputs; i++) {
if (vs->info.output_semantic_name[i] == TGSI_SEMANTIC_PSIZE) {
wide->psize_slot = i;
break;
}
}
}
stage->point( stage, header );
}
static void widepoint_flush( struct draw_stage *stage, unsigned flags )
{
struct draw_context *draw = stage->draw;
struct pipe_context *pipe = draw->pipe;
stage->point = widepoint_first_point;
stage->next->flush( stage->next, flags );
draw_remove_extra_vertex_attribs(draw);
/* restore original rasterizer state */
if (draw->rast_handle) {
draw->suspend_flushing = TRUE;
pipe->bind_rasterizer_state(pipe, draw->rast_handle);
draw->suspend_flushing = FALSE;
}
}
static void widepoint_reset_stipple_counter( struct draw_stage *stage )
{
stage->next->reset_stipple_counter( stage->next );
}
static void widepoint_destroy( struct draw_stage *stage )
{
draw_free_temp_verts( stage );
FREE( stage );
}
struct draw_stage *draw_wide_point_stage( struct draw_context *draw )
{
struct widepoint_stage *wide = CALLOC_STRUCT(widepoint_stage);
if (wide == NULL)
goto fail;
wide->stage.draw = draw;
wide->stage.name = "wide-point";
wide->stage.next = NULL;
wide->stage.point = widepoint_first_point;
wide->stage.line = draw_pipe_passthrough_line;
wide->stage.tri = draw_pipe_passthrough_tri;
wide->stage.flush = widepoint_flush;
wide->stage.reset_stipple_counter = widepoint_reset_stipple_counter;
wide->stage.destroy = widepoint_destroy;
if (!draw_alloc_temp_verts( &wide->stage, 4 ))
goto fail;
wide->sprite_coord_semantic =
draw->pipe->screen->get_param(draw->pipe->screen, PIPE_CAP_TGSI_TEXCOORD)
?
TGSI_SEMANTIC_TEXCOORD : TGSI_SEMANTIC_GENERIC;
return &wide->stage;
fail:
if (wide)
wide->stage.destroy( &wide->stage );
return NULL;
}