1 /*
2  * Copyright (C) 2014 Rob Clark <robclark@freedesktop.org>
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21  * SOFTWARE.
22  *
23  * Authors:
24  *    Rob Clark <robclark@freedesktop.org>
25  */
26 
27 #ifndef TGSI_LOWERING_H_
28 #define TGSI_LOWERING_H_
29 
30 #include "pipe/p_shader_tokens.h"
31 #include "tgsi/tgsi_scan.h"
32 
33 struct tgsi_lowering_config
34 {
35    /* For fragment shaders, generate a shader that emulates two
36     * sided color by inserting a BGCOLOR input for each COLOR
37     * input, and insert a CMP instruction to select the correct
38     * color to use based on the TGSI_SEMANTIC_FACE input.
39     *
40     * Note that drivers which use this to emulate two sided color
41     * will:
42     *  a) need to generate (on demand) alternate shaders to use
43     *     depending on the rasterizer state (ie. whether two
44     *     sided shading enabled)
45     *  b) expect to see the BGCOLOR semantic name in fragment
46     *     shaders.  During linkage, the driver should simply
47     *     map VS.OUT.BGCOLOR[n] to FS.IN.BGCOLOR[n] (in the
48     *     same was as linking other outs/ins).
49     */
50    unsigned color_two_side:1;
51 
52    /* TODO support for alpha_to_one as well?? */
53 
54    /* Individual OPC lowerings, if lower_<opc> is TRUE then
55     * enable lowering of TGSI_OPCODE_<opc>
56     */
57    unsigned lower_DST:1;
58    unsigned lower_LRP:1;
59    unsigned lower_FRC:1;
60    unsigned lower_POW:1;
61    unsigned lower_LIT:1;
62    unsigned lower_EXP:1;
63    unsigned lower_LOG:1;
64    unsigned lower_DP4:1;
65    unsigned lower_DP3:1;
66    unsigned lower_DP2:1;
67    unsigned lower_FLR:1;
68    unsigned lower_CEIL:1;
69    unsigned lower_TRUNC:1;
70 
71    /* bitmask of (1 << TGSI_TEXTURE_type): */
72    unsigned lower_TXP;
73 
74    /* To emulate certain texture wrap modes, this can be used
75     * to saturate the specified tex coord to [0.0, 1.0].  The
76     * bits are according to sampler #, ie. if, for example:
77     *
78     *   (conf->saturate_s & (1 << n))
79     *
80     * is true, then the s coord for sampler n is saturated.
81     */
82    unsigned saturate_s, saturate_t, saturate_r;
83 };
84 
85 const struct tgsi_token *
86 tgsi_transform_lowering(const struct tgsi_lowering_config *config,
87                         const struct tgsi_token *tokens,
88                         struct tgsi_shader_info *info);
89 
90 #endif /* FREEDRENO_LOWERING_H_ */
91