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 
50 struct 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  */
62 static inline boolean
shade_quad(struct quad_stage * qs,struct quad_header * quad)63 shade_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 
80 static void
coverage_quad(struct quad_stage * qs,struct quad_header * quad)81 coverage_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  */
103 static void
shade_quads(struct quad_stage * qs,struct quad_header * quads[],unsigned nr)104 shade_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  */
145 static void
shade_begin(struct quad_stage * qs)146 shade_begin(struct quad_stage *qs)
147 {
148    qs->next->begin(qs->next);
149 }
150 
151 
152 static void
shade_destroy(struct quad_stage * qs)153 shade_destroy(struct quad_stage *qs)
154 {
155    FREE( qs );
156 }
157 
158 
159 struct quad_stage *
sp_quad_shade_stage(struct softpipe_context * softpipe)160 sp_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 
173 fail:
174    FREE(qss);
175    return NULL;
176 }
177