1/**************************************************************************
2 *
3 * Copyright 2007 VMware, Inc.
4 * All Rights Reserved.
5 * Copyright 2008 VMware, Inc.  All rights reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the
9 * "Software"), to deal in the Software without restriction, including
10 * without limitation the rights to use, copy, modify, merge, publish,
11 * distribute, sub license, and/or sell copies of the Software, and to
12 * permit persons to whom the Software is furnished to do so, subject to
13 * the following conditions:
14 *
15 * The above copyright notice and this permission notice (including the
16 * next paragraph) shall be included in all copies or substantial portions
17 * of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
20 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
21 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
22 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
23 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
24 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
25 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26 *
27 **************************************************************************/
28
29/* Vertices are just an array of floats, with all the attributes
30 * packed.  We currently assume a layout like:
31 *
32 * attr[0][0..3] - window position
33 * attr[1..n][0..3] - remaining attributes.
34 *
35 * Attributes are assumed to be 4 floats wide but are packed so that
36 * all the enabled attributes run contiguously.
37 */
38
39#include "util/u_math.h"
40#include "util/u_memory.h"
41#include "pipe/p_defines.h"
42#include "pipe/p_shader_tokens.h"
43
44#include "sp_context.h"
45#include "sp_state.h"
46#include "sp_quad.h"
47#include "sp_quad_pipe.h"
48
49
50struct quad_shade_stage
51{
52   struct quad_stage stage;  /**< base class */
53
54   /* no other fields at this time */
55};
56
57
58/**
59 * Execute fragment shader for the four fragments in the quad.
60 * \return TRUE if quad is alive, FALSE if all four pixels are killed
61 */
62static inline boolean
63shade_quad(struct quad_stage *qs, struct quad_header *quad)
64{
65   struct softpipe_context *softpipe = qs->softpipe;
66   struct tgsi_exec_machine *machine = softpipe->fs_machine;
67
68   if (softpipe->active_statistics_queries) {
69      softpipe->pipeline_statistics.ps_invocations +=
70         util_bitcount(quad->inout.mask);
71   }
72
73   /* run shader */
74   machine->flatshade_color = softpipe->rasterizer->flatshade ? TRUE : FALSE;
75   return softpipe->fs_variant->run( softpipe->fs_variant, machine, quad, softpipe->early_depth );
76}
77
78
79
80static void
81coverage_quad(struct quad_stage *qs, struct quad_header *quad)
82{
83   struct softpipe_context *softpipe = qs->softpipe;
84   uint cbuf;
85
86   /* loop over colorbuffer outputs */
87   for (cbuf = 0; cbuf < softpipe->framebuffer.nr_cbufs; cbuf++) {
88      float (*quadColor)[4] = quad->output.color[cbuf];
89      unsigned j;
90      for (j = 0; j < TGSI_QUAD_SIZE; j++) {
91         assert(quad->input.coverage[j] >= 0.0);
92         assert(quad->input.coverage[j] <= 1.0);
93         quadColor[3][j] *= quad->input.coverage[j];
94      }
95   }
96}
97
98
99/**
100 * Shade/write an array of quads
101 * Called via quad_stage::run()
102 */
103static void
104shade_quads(struct quad_stage *qs,
105            struct quad_header *quads[],
106            unsigned nr)
107{
108   struct softpipe_context *softpipe = qs->softpipe;
109   struct tgsi_exec_machine *machine = softpipe->fs_machine;
110   unsigned i, nr_quads = 0;
111
112   tgsi_exec_set_constant_buffers(machine, PIPE_MAX_CONSTANT_BUFFERS,
113                         softpipe->mapped_constants[PIPE_SHADER_FRAGMENT],
114                         softpipe->const_buffer_size[PIPE_SHADER_FRAGMENT]);
115
116   machine->InterpCoefs = quads[0]->coef;
117
118   for (i = 0; i < nr; i++) {
119      /* Only omit this quad from the output list if all the fragments
120       * are killed _AND_ it's not the first quad in the list.
121       * The first quad is special in the (optimized) depth-testing code:
122       * the quads' Z coordinates are step-wise interpolated with respect
123       * to the first quad in the list.
124       * For multi-pass algorithms we need to produce exactly the same
125       * Z values in each pass.  If interpolation starts with different quads
126       * we can get different Z values for the same (x,y).
127       */
128      if (!shade_quad(qs, quads[i]) && i > 0)
129         continue; /* quad totally culled/killed */
130
131      if (/*do_coverage*/ 0)
132         coverage_quad( qs, quads[i] );
133
134      quads[nr_quads++] = quads[i];
135   }
136
137   if (nr_quads)
138      qs->next->run(qs->next, quads, nr_quads);
139}
140
141
142/**
143 * Per-primitive (or per-begin?) setup
144 */
145static void
146shade_begin(struct quad_stage *qs)
147{
148   qs->next->begin(qs->next);
149}
150
151
152static void
153shade_destroy(struct quad_stage *qs)
154{
155   FREE( qs );
156}
157
158
159struct quad_stage *
160sp_quad_shade_stage( struct softpipe_context *softpipe )
161{
162   struct quad_shade_stage *qss = CALLOC_STRUCT(quad_shade_stage);
163   if (!qss)
164      goto fail;
165
166   qss->stage.softpipe = softpipe;
167   qss->stage.begin = shade_begin;
168   qss->stage.run = shade_quads;
169   qss->stage.destroy = shade_destroy;
170
171   return &qss->stage;
172
173fail:
174   FREE(qss);
175   return NULL;
176}
177