/**************************************************************************
*
* 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.
*
**************************************************************************/
/**
* \brief Drawing stage for handling glPolygonMode(line/point).
* Convert triangles to points or lines as needed.
*/
/* Authors: Keith Whitwell <keithw@vmware.com>
*/
#include "util/u_memory.h"
#include "pipe/p_defines.h"
#include "draw_private.h"
#include "draw_pipe.h"
#include "draw_fs.h"
struct unfilled_stage {
struct draw_stage stage;
/** [0] = front face, [1] = back face.
* legal values: PIPE_POLYGON_MODE_FILL, PIPE_POLYGON_MODE_LINE,
* and PIPE_POLYGON_MODE_POINT,
*/
unsigned mode[2];
int face_slot;
};
static INLINE struct unfilled_stage *unfilled_stage( struct draw_stage *stage )
{
return (struct unfilled_stage *)stage;
}
static void
inject_front_face_info(struct draw_stage *stage,
struct prim_header *header)
{
struct unfilled_stage *unfilled = unfilled_stage(stage);
unsigned ccw = header->det < 0.0;
boolean is_front_face = (
(stage->draw->rasterizer->front_ccw && ccw) ||
(!stage->draw->rasterizer->front_ccw && !ccw));
int slot = unfilled->face_slot;
unsigned i;
/* In case the backend doesn't care about it */
if (slot < 0) {
return;
}
for (i = 0; i < 3; ++i) {
struct vertex_header *v = header->v[i];
v->data[slot][0] = is_front_face;
v->data[slot][1] = is_front_face;
v->data[slot][2] = is_front_face;
v->data[slot][3] = is_front_face;
v->vertex_id = UNDEFINED_VERTEX_ID;
}
}
static void point( struct draw_stage *stage,
struct vertex_header *v0 )
{
struct prim_header tmp;
tmp.v[0] = v0;
stage->next->point( stage->next, &tmp );
}
static void line( struct draw_stage *stage,
struct vertex_header *v0,
struct vertex_header *v1 )
{
struct prim_header tmp;
tmp.v[0] = v0;
tmp.v[1] = v1;
stage->next->line( stage->next, &tmp );
}
static void points( struct draw_stage *stage,
struct prim_header *header )
{
struct vertex_header *v0 = header->v[0];
struct vertex_header *v1 = header->v[1];
struct vertex_header *v2 = header->v[2];
inject_front_face_info(stage, header);
if ((header->flags & DRAW_PIPE_EDGE_FLAG_0) && v0->edgeflag) point( stage, v0 );
if ((header->flags & DRAW_PIPE_EDGE_FLAG_1) && v1->edgeflag) point( stage, v1 );
if ((header->flags & DRAW_PIPE_EDGE_FLAG_2) && v2->edgeflag) point( stage, v2 );
}
static void lines( struct draw_stage *stage,
struct prim_header *header )
{
struct vertex_header *v0 = header->v[0];
struct vertex_header *v1 = header->v[1];
struct vertex_header *v2 = header->v[2];
if (header->flags & DRAW_PIPE_RESET_STIPPLE)
stage->next->reset_stipple_counter( stage->next );
inject_front_face_info(stage, header);
if ((header->flags & DRAW_PIPE_EDGE_FLAG_2) && v2->edgeflag) line( stage, v2, v0 );
if ((header->flags & DRAW_PIPE_EDGE_FLAG_0) && v0->edgeflag) line( stage, v0, v1 );
if ((header->flags & DRAW_PIPE_EDGE_FLAG_1) && v1->edgeflag) line( stage, v1, v2 );
}
/** For debugging */
static void
print_header_flags(unsigned flags)
{
debug_printf("header->flags = ");
if (flags & DRAW_PIPE_RESET_STIPPLE)
debug_printf("RESET_STIPPLE ");
if (flags & DRAW_PIPE_EDGE_FLAG_0)
debug_printf("EDGE_FLAG_0 ");
if (flags & DRAW_PIPE_EDGE_FLAG_1)
debug_printf("EDGE_FLAG_1 ");
if (flags & DRAW_PIPE_EDGE_FLAG_2)
debug_printf("EDGE_FLAG_2 ");
debug_printf("\n");
}
/* Unfilled tri:
*
* Note edgeflags in the vertex struct is not sufficient as we will
* need to manipulate them when decomposing primitives.
*
* We currently keep the vertex edgeflag and primitive edgeflag mask
* separate until the last possible moment.
*/
static void unfilled_tri( struct draw_stage *stage,
struct prim_header *header )
{
struct unfilled_stage *unfilled = unfilled_stage(stage);
unsigned cw = header->det >= 0.0;
unsigned mode = unfilled->mode[cw];
if (0)
print_header_flags(header->flags);
switch (mode) {
case PIPE_POLYGON_MODE_FILL:
stage->next->tri( stage->next, header );
break;
case PIPE_POLYGON_MODE_LINE:
lines( stage, header );
break;
case PIPE_POLYGON_MODE_POINT:
points( stage, header );
break;
default:
}
}
static void unfilled_first_tri( struct draw_stage *stage,
struct prim_header *header )
{
struct unfilled_stage *unfilled = unfilled_stage(stage);
const struct pipe_rasterizer_state *rast = stage->draw->rasterizer;
unfilled->mode[0] = rast->front_ccw ? rast->fill_front : rast->fill_back;
unfilled->mode[1] = rast->front_ccw ? rast->fill_back : rast->fill_front;
stage->tri = unfilled_tri;
stage->tri( stage, header );
}
static void unfilled_flush( struct draw_stage *stage,
unsigned flags )
{
stage->next->flush( stage->next, flags );
stage->tri = unfilled_first_tri;
}
static void unfilled_reset_stipple_counter( struct draw_stage *stage )
{
stage->next->reset_stipple_counter( stage->next );
}
static void unfilled_destroy( struct draw_stage *stage )
{
draw_free_temp_verts( stage );
FREE( stage );
}
/*
* Try to allocate an output slot which we can use
* to preserve the front face information.
*/
void
draw_unfilled_prepare_outputs( struct draw_context *draw,
struct draw_stage *stage )
{
struct unfilled_stage *unfilled = unfilled_stage(stage);
const struct pipe_rasterizer_state *rast = draw ? draw->rasterizer : 0;
boolean is_unfilled = (rast &&
(rast->fill_front != PIPE_POLYGON_MODE_FILL ||
rast->fill_back != PIPE_POLYGON_MODE_FILL));
const struct draw_fragment_shader *fs = draw ? draw->fs.fragment_shader : 0;
if (is_unfilled && fs && fs->info.uses_frontface) {
unfilled->face_slot = draw_alloc_extra_vertex_attrib(
stage->draw, TGSI_SEMANTIC_FACE, 0);
} else {
unfilled->face_slot = -1;
}
}
/**
* Create unfilled triangle stage.
*/
struct draw_stage *draw_unfilled_stage( struct draw_context *draw )
{
struct unfilled_stage *unfilled = CALLOC_STRUCT(unfilled_stage);
if (unfilled == NULL)
goto fail;
unfilled->stage.draw = draw;
unfilled->stage.name = "unfilled";
unfilled->stage.next = NULL;
unfilled->stage.tmp = NULL;
unfilled->stage.point = draw_pipe_passthrough_point;
unfilled->stage.line = draw_pipe_passthrough_line;
unfilled->stage.tri = unfilled_first_tri;
unfilled->stage.flush = unfilled_flush;
unfilled->stage.reset_stipple_counter = unfilled_reset_stipple_counter;
unfilled->stage.destroy = unfilled_destroy;
unfilled->face_slot = -1;
if (!draw_alloc_temp_verts( &unfilled->stage, 0 ))
goto fail;
return &unfilled->stage;
fail:
if (unfilled)
unfilled->stage.destroy( &unfilled->stage );
return NULL;
}