1 /*
2  * Copyright 2019 Advanced Micro Devices, Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the
6  * "Software"), to deal in the Software without restriction, including
7  * without limitation the rights to use, copy, modify, merge, publish,
8  * distribute, sub license, and/or sell copies of the Software, and to
9  * permit persons to whom the Software is furnished to do so, subject to
10  * the following conditions:
11  *
12  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
13  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
14  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
15  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
16  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
17  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
18  * USE OR OTHER DEALINGS IN THE SOFTWARE.
19  *
20  * The above copyright notice and this permission notice (including the
21  * next paragraph) shall be included in all copies or substantial portions
22  * of the Software.
23  *
24  */
25 
26 #ifndef AC_LLVM_CULL_H
27 #define AC_LLVM_CULL_H
28 
29 #include "ac_llvm_build.h"
30 
31 struct ac_cull_options {
32    /* In general, I recommend setting all to true except view Z culling,
33     * which isn't so effective because W culling is cheaper and partially
34     * replaces near Z culling, and you don't need to set Position.z
35     * if Z culling is disabled.
36     *
37     * If something doesn't work, turn some of these off to find out what.
38     */
39    bool cull_front;
40    bool cull_back;
41    bool cull_view_xy;
42    bool cull_view_near_z;
43    bool cull_view_far_z;
44    bool cull_small_prims;
45    bool cull_zero_area;
46    bool cull_w; /* cull primitives with all W < 0 */
47 
48    bool use_halfz_clip_space;
49 
50    uint8_t num_vertices; /* 1..3 */
51 };
52 
53 /* Callback invoked in the inner-most branch where the primitive is accepted. */
54 typedef void (*ac_cull_accept_func)(struct ac_llvm_context *ctx, LLVMValueRef accepted,
55                                     void *userdata);
56 
57 void ac_cull_primitive(struct ac_llvm_context *ctx, LLVMValueRef pos[3][4],
58                        LLVMValueRef initially_accepted, LLVMValueRef vp_scale[2],
59                        LLVMValueRef vp_translate[2], LLVMValueRef small_prim_precision,
60                        LLVMValueRef clip_half_line_width[2], struct ac_cull_options *options,
61                        ac_cull_accept_func accept_func, void *userdata);
62 
63 #endif
64