1/**************************************************************************
2 *
3 * Copyright 2010 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 THE AUTHORS 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/**
30 * Transform feedback functions.
31 *
32 * \author Brian Paul
33 *         Marek Olšák
34 */
35
36
37#include "main/bufferobj.h"
38#include "main/context.h"
39#include "main/transformfeedback.h"
40
41#include "st_cb_bufferobjects.h"
42#include "st_cb_xformfb.h"
43#include "st_context.h"
44
45#include "pipe/p_context.h"
46#include "util/u_draw.h"
47#include "util/u_inlines.h"
48#include "cso_cache/cso_context.h"
49
50struct st_transform_feedback_object {
51   struct gl_transform_feedback_object base;
52
53   unsigned num_targets;
54   struct pipe_stream_output_target *targets[PIPE_MAX_SO_BUFFERS];
55
56   /* This encapsulates the count that can be used as a source for draw_vbo.
57    * It contains stream output targets from the last call of
58    * EndTransformFeedback for each stream. */
59   struct pipe_stream_output_target *draw_count[MAX_VERTEX_STREAMS];
60};
61
62static inline struct st_transform_feedback_object *
63st_transform_feedback_object(struct gl_transform_feedback_object *obj)
64{
65   return (struct st_transform_feedback_object *) obj;
66}
67
68static struct gl_transform_feedback_object *
69st_new_transform_feedback(struct gl_context *ctx, GLuint name)
70{
71   struct st_transform_feedback_object *obj;
72
73   obj = CALLOC_STRUCT(st_transform_feedback_object);
74   if (!obj)
75      return NULL;
76
77   _mesa_init_transform_feedback_object(&obj->base, name);
78
79   return &obj->base;
80}
81
82
83static void
84st_delete_transform_feedback(struct gl_context *ctx,
85                             struct gl_transform_feedback_object *obj)
86{
87   struct st_transform_feedback_object *sobj =
88         st_transform_feedback_object(obj);
89   unsigned i;
90
91   for (i = 0; i < ARRAY_SIZE(sobj->draw_count); i++)
92      pipe_so_target_reference(&sobj->draw_count[i], NULL);
93
94   /* Unreference targets. */
95   for (i = 0; i < sobj->num_targets; i++) {
96      pipe_so_target_reference(&sobj->targets[i], NULL);
97   }
98
99   for (i = 0; i < ARRAY_SIZE(sobj->base.Buffers); i++) {
100      _mesa_reference_buffer_object(ctx, &sobj->base.Buffers[i], NULL);
101   }
102
103   free(obj);
104}
105
106
107/* XXX Do we really need the mode? */
108static void
109st_begin_transform_feedback(struct gl_context *ctx, GLenum mode,
110                            struct gl_transform_feedback_object *obj)
111{
112   struct st_context *st = st_context(ctx);
113   struct pipe_context *pipe = st->pipe;
114   struct st_transform_feedback_object *sobj =
115         st_transform_feedback_object(obj);
116   unsigned i, max_num_targets;
117   unsigned offsets[PIPE_MAX_SO_BUFFERS] = {0};
118
119   max_num_targets = MIN2(ARRAY_SIZE(sobj->base.Buffers),
120                          ARRAY_SIZE(sobj->targets));
121
122   /* Convert the transform feedback state into the gallium representation. */
123   for (i = 0; i < max_num_targets; i++) {
124      struct st_buffer_object *bo = st_buffer_object(sobj->base.Buffers[i]);
125
126      if (bo && bo->buffer) {
127         unsigned stream = obj->program->sh.LinkedTransformFeedback->
128            Buffers[i].Stream;
129
130         /* Check whether we need to recreate the target. */
131         if (!sobj->targets[i] ||
132             sobj->targets[i] == sobj->draw_count[stream] ||
133             sobj->targets[i]->buffer != bo->buffer ||
134             sobj->targets[i]->buffer_offset != sobj->base.Offset[i] ||
135             sobj->targets[i]->buffer_size != sobj->base.Size[i]) {
136            /* Create a new target. */
137            struct pipe_stream_output_target *so_target =
138                  pipe->create_stream_output_target(pipe, bo->buffer,
139                                                    sobj->base.Offset[i],
140                                                    sobj->base.Size[i]);
141
142            pipe_so_target_reference(&sobj->targets[i], NULL);
143            sobj->targets[i] = so_target;
144         }
145
146         sobj->num_targets = i+1;
147      } else {
148         pipe_so_target_reference(&sobj->targets[i], NULL);
149      }
150   }
151
152   /* Start writing at the beginning of each target. */
153   cso_set_stream_outputs(st->cso_context, sobj->num_targets,
154                          sobj->targets, offsets);
155}
156
157
158static void
159st_pause_transform_feedback(struct gl_context *ctx,
160                           struct gl_transform_feedback_object *obj)
161{
162   struct st_context *st = st_context(ctx);
163   cso_set_stream_outputs(st->cso_context, 0, NULL, NULL);
164}
165
166
167static void
168st_resume_transform_feedback(struct gl_context *ctx,
169                             struct gl_transform_feedback_object *obj)
170{
171   struct st_context *st = st_context(ctx);
172   struct st_transform_feedback_object *sobj =
173      st_transform_feedback_object(obj);
174   unsigned offsets[PIPE_MAX_SO_BUFFERS];
175   unsigned i;
176
177   for (i = 0; i < PIPE_MAX_SO_BUFFERS; i++)
178      offsets[i] = (unsigned)-1;
179
180   cso_set_stream_outputs(st->cso_context, sobj->num_targets,
181                          sobj->targets, offsets);
182}
183
184
185static void
186st_end_transform_feedback(struct gl_context *ctx,
187                          struct gl_transform_feedback_object *obj)
188{
189   struct st_context *st = st_context(ctx);
190   struct st_transform_feedback_object *sobj =
191         st_transform_feedback_object(obj);
192   unsigned i;
193
194   cso_set_stream_outputs(st->cso_context, 0, NULL, NULL);
195
196   /* The next call to glDrawTransformFeedbackStream should use the vertex
197    * count from the last call to glEndTransformFeedback.
198    * Therefore, save the targets for each stream.
199    *
200    * NULL means the vertex counter is 0 (initial state).
201    */
202   for (i = 0; i < ARRAY_SIZE(sobj->draw_count); i++)
203      pipe_so_target_reference(&sobj->draw_count[i], NULL);
204
205   for (i = 0; i < ARRAY_SIZE(sobj->targets); i++) {
206      unsigned stream = obj->program->sh.LinkedTransformFeedback->
207         Buffers[i].Stream;
208
209      /* Is it not bound or already set for this stream? */
210      if (!sobj->targets[i] || sobj->draw_count[stream])
211         continue;
212
213      pipe_so_target_reference(&sobj->draw_count[stream], sobj->targets[i]);
214   }
215}
216
217
218bool
219st_transform_feedback_draw_init(struct gl_transform_feedback_object *obj,
220                                unsigned stream, struct pipe_draw_info *out)
221{
222   struct st_transform_feedback_object *sobj =
223         st_transform_feedback_object(obj);
224
225   out->count_from_stream_output = sobj->draw_count[stream];
226   return out->count_from_stream_output != NULL;
227}
228
229
230void
231st_init_xformfb_functions(struct dd_function_table *functions)
232{
233   functions->NewTransformFeedback = st_new_transform_feedback;
234   functions->DeleteTransformFeedback = st_delete_transform_feedback;
235   functions->BeginTransformFeedback = st_begin_transform_feedback;
236   functions->EndTransformFeedback = st_end_transform_feedback;
237   functions->PauseTransformFeedback = st_pause_transform_feedback;
238   functions->ResumeTransformFeedback = st_resume_transform_feedback;
239}
240