1/**************************************************************************
2 *
3 * Copyright 2009 VMware, Inc.
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27
28/**
29 * @file
30 * Position and shader input interpolation.
31 *
32 * Special attention is given to the interpolation of side by side quads.
33 * Multiplications are made only for the first quad. Interpolation of
34 * inputs for posterior quads are done exclusively with additions, and
35 * perspective divide if necessary.
36 *
37 * @author Jose Fonseca <jfonseca@vmware.com>
38 */
39
40#ifndef LP_BLD_INTERP_H
41#define LP_BLD_INTERP_H
42
43
44#include "gallivm/lp_bld.h"
45#include "gallivm/lp_bld_type.h"
46
47#include "tgsi/tgsi_exec.h"
48
49/**
50 * Describes how to compute the interpolation coefficients (a0, dadx, dady)
51 * from the vertices passed into our triangle/line/point functions by the
52 * draw module.
53 *
54 * Vertices are treated as an array of float[4] values, indexed by
55 * src_index.
56 *
57 * LP_INTERP_COLOR is translated to either LP_INTERP_CONSTANT or
58 * PERSPECTIVE depending on flatshade state.
59 */
60enum lp_interp {
61   LP_INTERP_CONSTANT,
62   LP_INTERP_COLOR,
63   LP_INTERP_LINEAR,
64   LP_INTERP_PERSPECTIVE,
65   LP_INTERP_POSITION,
66   LP_INTERP_FACING
67};
68
69struct lp_shader_input {
70   uint interp:4;       /* enum lp_interp */
71   uint usage_mask:4;   /* bitmask of TGSI_WRITEMASK_x flags */
72   uint src_index:8;    /* where to find values in incoming vertices */
73   uint location:2;     /* TGSI_INTERPOLATE_LOC_* */
74   uint padding:14;
75};
76
77
78struct lp_build_interp_soa_context
79{
80   /* TGSI_QUAD_SIZE x float */
81   struct lp_build_context coeff_bld;
82   struct lp_build_context setup_bld;
83
84   unsigned num_attribs;
85   unsigned mask[1 + PIPE_MAX_SHADER_INPUTS]; /**< TGSI_WRITE_MASK_x */
86   enum lp_interp interp[1 + PIPE_MAX_SHADER_INPUTS];
87   unsigned interp_loc[1 + PIPE_MAX_SHADER_INPUTS];
88   boolean depth_clamp;
89
90   double pos_offset;
91   unsigned coverage_samples;
92   LLVMValueRef num_loop;
93   LLVMValueRef sample_pos_array;
94
95   LLVMValueRef x;
96   LLVMValueRef y;
97
98   LLVMValueRef a0_ptr;
99   LLVMValueRef dadx_ptr;
100   LLVMValueRef dady_ptr;
101
102   LLVMValueRef a0aos[1 + PIPE_MAX_SHADER_INPUTS];
103   LLVMValueRef dadxaos[1 + PIPE_MAX_SHADER_INPUTS];
104   LLVMValueRef dadyaos[1 + PIPE_MAX_SHADER_INPUTS];
105
106   LLVMValueRef attribs[1 + PIPE_MAX_SHADER_INPUTS][TGSI_NUM_CHANNELS];
107
108   LLVMValueRef xoffset_store;
109   LLVMValueRef yoffset_store;
110   LLVMTypeRef store_elem_type;
111
112   /*
113    * Convenience pointers. Callers may access this one.
114    */
115   const LLVMValueRef *pos;
116   const LLVMValueRef (*inputs)[TGSI_NUM_CHANNELS];
117};
118
119
120void
121lp_build_interp_soa_init(struct lp_build_interp_soa_context *bld,
122                         struct gallivm_state *gallivm,
123                         unsigned num_inputs,
124                         const struct lp_shader_input *inputs,
125                         boolean pixel_center_integer,
126                         unsigned coverage_samples,
127                         LLVMValueRef sample_pos_array,
128                         LLVMValueRef num_loop,
129                         LLVMBuilderRef builder,
130                         struct lp_type type,
131                         LLVMValueRef a0_ptr,
132                         LLVMValueRef dadx_ptr,
133                         LLVMValueRef dady_ptr,
134                         LLVMValueRef x,
135                         LLVMValueRef y);
136
137void
138lp_build_interp_soa_update_inputs_dyn(struct lp_build_interp_soa_context *bld,
139                                      struct gallivm_state *gallivm,
140                                      LLVMValueRef quad_start_index,
141                                      LLVMValueRef mask_store,
142                                      LLVMValueRef sample_id);
143
144void
145lp_build_interp_soa_update_pos_dyn(struct lp_build_interp_soa_context *bld,
146                                   struct gallivm_state *gallivm,
147                                   LLVMValueRef quad_start_index,
148                                   LLVMValueRef sample_id);
149
150LLVMValueRef
151lp_build_interp_soa(struct lp_build_interp_soa_context *bld,
152                    struct gallivm_state *gallivm,
153                    LLVMValueRef loop_iter,
154                    LLVMValueRef mask_store,
155                    unsigned attrib, unsigned chan,
156                    unsigned loc,
157                    LLVMValueRef indir_index,
158                    LLVMValueRef offsets[2]);
159
160#endif /* LP_BLD_INTERP_H */
161