1 /*
2 * Copyright © 2012 Intel Corporation
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
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 *
23 * Authors:
24 * Jordan Justen <jordan.l.justen@intel.com>
25 *
26 */
27
28 #include "main/imports.h"
29 #include "main/bufferobj.h"
30 #include "main/varray.h"
31 #include "vbo/vbo.h"
32
33 #include "brw_context.h"
34 #include "brw_defines.h"
35 #include "brw_draw.h"
36
37 #include "intel_batchbuffer.h"
38
39 /**
40 * Check if the hardware's cut index support can handle the primitive
41 * restart index value (pre-Haswell only).
42 */
43 static bool
can_cut_index_handle_restart_index(struct gl_context * ctx,const struct _mesa_index_buffer * ib)44 can_cut_index_handle_restart_index(struct gl_context *ctx,
45 const struct _mesa_index_buffer *ib)
46 {
47 /* The FixedIndex variant means 0xFF, 0xFFFF, or 0xFFFFFFFF based on
48 * the index buffer type, which corresponds exactly to the hardware.
49 */
50 if (ctx->Array.PrimitiveRestartFixedIndex)
51 return true;
52
53 bool cut_index_will_work;
54
55 switch (ib->index_size) {
56 case 1:
57 cut_index_will_work = ctx->Array.RestartIndex == 0xff;
58 break;
59 case 2:
60 cut_index_will_work = ctx->Array.RestartIndex == 0xffff;
61 break;
62 case 4:
63 cut_index_will_work = ctx->Array.RestartIndex == 0xffffffff;
64 break;
65 default:
66 unreachable("not reached");
67 }
68
69 return cut_index_will_work;
70 }
71
72 /**
73 * Check if the hardware's cut index support can handle the primitive
74 * restart case.
75 */
76 static bool
can_cut_index_handle_prims(struct gl_context * ctx,const struct _mesa_prim * prim,GLuint nr_prims,const struct _mesa_index_buffer * ib)77 can_cut_index_handle_prims(struct gl_context *ctx,
78 const struct _mesa_prim *prim,
79 GLuint nr_prims,
80 const struct _mesa_index_buffer *ib)
81 {
82 struct brw_context *brw = brw_context(ctx);
83 const struct gen_device_info *devinfo = &brw->screen->devinfo;
84
85 /* Otherwise Haswell can do it all. */
86 if (devinfo->gen >= 8 || devinfo->is_haswell)
87 return true;
88
89 if (!can_cut_index_handle_restart_index(ctx, ib)) {
90 /* The primitive restart index can't be handled, so take
91 * the software path
92 */
93 return false;
94 }
95
96 for (unsigned i = 0; i < nr_prims; i++) {
97 switch (prim[i].mode) {
98 case GL_POINTS:
99 case GL_LINES:
100 case GL_LINE_STRIP:
101 case GL_TRIANGLES:
102 case GL_TRIANGLE_STRIP:
103 case GL_LINES_ADJACENCY:
104 case GL_LINE_STRIP_ADJACENCY:
105 case GL_TRIANGLES_ADJACENCY:
106 case GL_TRIANGLE_STRIP_ADJACENCY:
107 /* Cut index supports these primitive types */
108 break;
109 default:
110 /* Cut index does not support these primitive types */
111 //case GL_LINE_LOOP:
112 //case GL_TRIANGLE_FAN:
113 //case GL_QUADS:
114 //case GL_QUAD_STRIP:
115 //case GL_POLYGON:
116 return false;
117 }
118 }
119
120 return true;
121 }
122
123 /**
124 * Check if primitive restart is enabled, and if so, handle it properly.
125 *
126 * In some cases the support will be handled in software. When available
127 * hardware will handle primitive restart.
128 */
129 GLboolean
brw_handle_primitive_restart(struct gl_context * ctx,const struct _mesa_prim * prims,GLuint nr_prims,const struct _mesa_index_buffer * ib,struct gl_buffer_object * indirect)130 brw_handle_primitive_restart(struct gl_context *ctx,
131 const struct _mesa_prim *prims,
132 GLuint nr_prims,
133 const struct _mesa_index_buffer *ib,
134 struct gl_buffer_object *indirect)
135 {
136 struct brw_context *brw = brw_context(ctx);
137
138 /* We only need to handle cases where there is an index buffer. */
139 if (ib == NULL) {
140 return GL_FALSE;
141 }
142
143 /* If we have set the in_progress flag, then we are in the middle
144 * of handling the primitive restart draw.
145 */
146 if (brw->prim_restart.in_progress) {
147 return GL_FALSE;
148 }
149
150 /* If PrimitiveRestart is not enabled, then we aren't concerned about
151 * handling this draw.
152 */
153 if (!(ctx->Array._PrimitiveRestart)) {
154 return GL_FALSE;
155 }
156
157 /* Signal that we are in the process of handling the
158 * primitive restart draw
159 */
160 brw->prim_restart.in_progress = true;
161
162 if (can_cut_index_handle_prims(ctx, prims, nr_prims, ib)) {
163 /* Cut index should work for primitive restart, so use it
164 */
165 brw->prim_restart.enable_cut_index = true;
166 brw_draw_prims(ctx, prims, nr_prims, ib, GL_FALSE, -1, -1, NULL, 0,
167 indirect);
168 brw->prim_restart.enable_cut_index = false;
169 } else {
170 /* Not all the primitive draw modes are supported by the cut index,
171 * so take the software path
172 */
173 vbo_sw_primitive_restart(ctx, prims, nr_prims, ib, indirect);
174 }
175
176 brw->prim_restart.in_progress = false;
177
178 /* The primitive restart draw was completed, so return true. */
179 return GL_TRUE;
180 }
181