u_primconvert.c revision af69d88d 
1/*
2 * Copyright (C) 2013 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/**
28 * This module converts provides a more convenient front-end to u_indices,
29 * etc, utils to convert primitive types supported not supported by the
30 * hardware.  It handles binding new index buffer state, and restoring
31 * previous state after.  To use, put something like this at the front of
32 * drivers pipe->draw_vbo():
33 *
34 *    // emulate unsupported primitives:
35 *    if (info->mode needs emulating) {
36 *       util_primconvert_save_index_buffer(ctx->primconvert, &ctx->indexbuf);
37 *       util_primconvert_save_rasterizer_state(ctx->primconvert, ctx->rasterizer);
38 *       util_primconvert_draw_vbo(ctx->primconvert, info);
39 *       return;
40 *    }
41 *
42 */
43
44#include "pipe/p_state.h"
45#include "util/u_draw.h"
46#include "util/u_inlines.h"
47#include "util/u_memory.h"
48
49#include "indices/u_indices.h"
50#include "indices/u_primconvert.h"
51
52struct primconvert_context
53{
54   struct pipe_context *pipe;
55   struct pipe_index_buffer saved_ib;
56   uint32_t primtypes_mask;
57   unsigned api_pv;
58   // TODO we could cache/recycle the indexbuf created to translate prims..
59};
60
61
62struct primconvert_context *
63util_primconvert_create(struct pipe_context *pipe, uint32_t primtypes_mask)
64{
65   struct primconvert_context *pc = CALLOC_STRUCT(primconvert_context);
66   if (!pc)
67      return NULL;
68   pc->pipe = pipe;
69   pc->primtypes_mask = primtypes_mask;
70   return pc;
71}
72
73void
74util_primconvert_destroy(struct primconvert_context *pc)
75{
76   util_primconvert_save_index_buffer(pc, NULL);
77   FREE(pc);
78}
79
80void
81util_primconvert_save_index_buffer(struct primconvert_context *pc,
82                                   const struct pipe_index_buffer *ib)
83{
84   if (ib) {
85      pipe_resource_reference(&pc->saved_ib.buffer, ib->buffer);
86      pc->saved_ib.index_size = ib->index_size;
87      pc->saved_ib.offset = ib->offset;
88      pc->saved_ib.user_buffer = ib->user_buffer;
89   }
90   else {
91      pipe_resource_reference(&pc->saved_ib.buffer, NULL);
92   }
93}
94
95void
96util_primconvert_save_rasterizer_state(struct primconvert_context *pc,
97                                       const struct pipe_rasterizer_state
98                                       *rast)
99{
100   /* if we actually translated the provoking vertex for the buffer,
101    * we would actually need to save/restore rasterizer state.  As
102    * it is, we just need to make note of the pv.
103    */
104   pc->api_pv = (rast->flatshade
105                 && !rast->flatshade_first) ? PV_LAST : PV_FIRST;
106}
107
108void
109util_primconvert_draw_vbo(struct primconvert_context *pc,
110                          const struct pipe_draw_info *info)
111{
112   struct pipe_index_buffer *ib = &pc->saved_ib;
113   struct pipe_index_buffer new_ib;
114   struct pipe_draw_info new_info;
115   struct pipe_transfer *src_transfer = NULL, *dst_transfer = NULL;
116   u_translate_func trans_func;
117   u_generate_func gen_func;
118   const void *src;
119   void *dst;
120
121   memset(&new_ib, 0, sizeof(new_ib));
122   util_draw_init_info(&new_info);
123   new_info.indexed = true;
124   new_info.min_index = info->min_index;
125   new_info.max_index = info->max_index;
126
127   if (info->indexed) {
128      u_index_translator(pc->primtypes_mask,
129                         info->mode, pc->saved_ib.index_size, info->count,
130                         pc->api_pv, pc->api_pv,
131                         &new_info.mode, &new_ib.index_size, &new_info.count,
132                         &trans_func);
133      src = ib->user_buffer;
134      if (!src) {
135         src = pipe_buffer_map(pc->pipe, ib->buffer,
136                               PIPE_TRANSFER_READ, &src_transfer);
137      }
138   }
139   else {
140      u_index_generator(pc->primtypes_mask,
141                        info->mode, info->start, info->count,
142                        pc->api_pv, pc->api_pv,
143                        &new_info.mode, &new_ib.index_size, &new_info.count,
144                        &gen_func);
145   }
146
147
148   new_ib.buffer = pipe_buffer_create(pc->pipe->screen,
149                                      PIPE_BIND_INDEX_BUFFER,
150                                      PIPE_USAGE_IMMUTABLE,
151                                      new_ib.index_size * new_info.count);
152   dst =
153      pipe_buffer_map(pc->pipe, new_ib.buffer, PIPE_TRANSFER_WRITE,
154                      &dst_transfer);
155
156   if (info->indexed) {
157      trans_func(src, info->start, new_info.count, dst);
158   }
159   else {
160      gen_func(info->start, new_info.count, dst);
161   }
162
163   if (src_transfer)
164      pipe_buffer_unmap(pc->pipe, src_transfer);
165
166   if (dst_transfer)
167      pipe_buffer_unmap(pc->pipe, dst_transfer);
168
169   /* bind new index buffer: */
170   pc->pipe->set_index_buffer(pc->pipe, &new_ib);
171
172   /* to the translated draw: */
173   pc->pipe->draw_vbo(pc->pipe, &new_info);
174
175   /* and then restore saved ib: */
176   pc->pipe->set_index_buffer(pc->pipe, ib);
177
178   pipe_resource_reference(&new_ib.buffer, NULL);
179}
180