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| -rw-r--r-- | src/mesa/pipe/draw/draw_feedback.c | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/src/mesa/pipe/draw/draw_feedback.c b/src/mesa/pipe/draw/draw_feedback.c new file mode 100644 index 0000000000..2729f44dc6 --- /dev/null +++ b/src/mesa/pipe/draw/draw_feedback.c @@ -0,0 +1,247 @@ +/************************************************************************** + * + * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas. + * All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sub license, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. + * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR + * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, + * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE + * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + **************************************************************************/ + +/** + * Primitive/vertex feedback (and/or discard) stage. + * Used to implement transformation feedback/streaming and other things + * which require a post-transformed vertex position (such as rasterpos, + * selection and feedback modes). + * + * Authors: + * Brian Paul + */ + + +#include "pipe/p_util.h" +#include "draw_private.h" + + +struct feedback_stage { + struct draw_stage stage; /**< base class */ + uint num_prim_generated; /**< number of primitives received */ + uint num_prim_emitted; /**< number of primitives fed back */ + uint num_vert_emitted; /**< number of vertices fed back */ + uint max_vert_emit; /**< max number of verts we can emit */ + float *dest[PIPE_MAX_FEEDBACK_ATTRIBS]; /**< dests for vertex attribs */ +}; + + + +/** + * Check if there's space to store 'numVerts' in the feedback buffer(s). + */ +static boolean +check_space(const struct draw_stage *stage, uint numVerts) +{ + const struct feedback_stage *fs = (struct feedback_stage *) stage; + return fs->num_vert_emitted + numVerts <= fs->max_vert_emit; +} + + +/** + * Record the given vertex's attributes into the feedback buffer(s). + */ +static void +feedback_vertex(struct draw_stage *stage, const struct vertex_header *vertex) +{ + struct feedback_stage *fs = (struct feedback_stage *) stage; + const struct pipe_feedback_state *feedback = &stage->draw->feedback; + const uint select = feedback->interleaved ? 0 : 1; + uint i; + + /* + * Note: 'select' is either 0 or 1. By multiplying 'i' by 'select' + * we can either address output buffer 0 (for interleaving) or + * output buffer i (for non-interleaved). + */ + + for (i = 0; i < feedback->num_attribs; i++) { + const uint attr = feedback->attrib[i]; + const float *src = attr ? vertex->data[attr] : vertex->clip; + const uint size = feedback->size[i]; + float *dest = fs->dest[i * select]; + + switch (size) { + case 4: + dest[3] = src[3]; + /* fall-through */ + case 3: + dest[2] = src[2]; + /* fall-through */ + case 2: + dest[1] = src[1]; + /* fall-through */ + case 1: + dest[0] = src[0]; + /* fall-through */ + default: + ; + } + fs->dest[i * select] += size; + } + + fs->num_vert_emitted++; +} + + +static void feedback_begin( struct draw_stage *stage ) +{ + struct feedback_stage *fs = (struct feedback_stage *) stage; + const struct pipe_feedback_state *feedback = &stage->draw->feedback; + + fs->num_prim_generated = 0; + fs->num_prim_emitted = 0; + fs->num_vert_emitted = 0; + + assert(feedback->enabled); + + /* Compute max_vert_emit, the max number of vertices we can emit. + * And, setup dest[] pointers. + */ + if (stage->draw->feedback.interleaved) { + uint i, vertex_size = 0; + /* compute size of each interleaved vertex, in floats */ + for (i = 0; i < feedback->num_attribs; i++) { + vertex_size += feedback->size[i]; + } + /* compute max number of vertices we can feedback */ + fs->max_vert_emit = stage->draw->mapped_feedback_buffer_size[0] + / sizeof(float) / vertex_size; + + fs->dest[0] = (float *) stage->draw->mapped_feedback_buffer[0]; + } + else { + uint i; + uint max = ~0; + for (i = 0; i < feedback->num_attribs; i++) { + uint n = stage->draw->mapped_feedback_buffer_size[i] + / sizeof(float) / feedback->size[i]; + if (n < max) + max = n; + fs->dest[i] = (float *) stage->draw->mapped_feedback_buffer[i]; + } + fs->max_vert_emit = max; + } + + if (!feedback->discard) + stage->next->begin( stage->next ); +} + + +static void feedback_tri( struct draw_stage *stage, + struct prim_header *header ) +{ + struct feedback_stage *fs = (struct feedback_stage *) stage; + + fs->num_prim_generated++; + + if (stage->draw->feedback.enabled && check_space(stage, 3)) { + feedback_vertex(stage, header->v[0]); + feedback_vertex(stage, header->v[1]); + feedback_vertex(stage, header->v[2]); + fs->num_prim_emitted++; + } + + if (!stage->draw->feedback.discard) + stage->next->tri( stage->next, header ); +} + + +static void feedback_line( struct draw_stage *stage, + struct prim_header *header ) +{ + struct feedback_stage *fs = (struct feedback_stage *) stage; + + fs->num_prim_generated++; + + if (stage->draw->feedback.enabled && check_space(stage, 2)) { + feedback_vertex(stage, header->v[0]); + feedback_vertex(stage, header->v[1]); + fs->num_prim_emitted++; + } + + if (!stage->draw->feedback.discard) + stage->next->line( stage->next, header ); +} + + +static void feedback_point( struct draw_stage *stage, + struct prim_header *header ) +{ + struct feedback_stage *fs = (struct feedback_stage *) stage; + + fs->num_prim_generated++; + + if (stage->draw->feedback.enabled && check_space(stage, 1)) { + feedback_vertex(stage, header->v[0]); + fs->num_prim_emitted++; + } + + if (!stage->draw->feedback.discard) + stage->next->point( stage->next, header ); +} + + +static void feedback_end( struct draw_stage *stage ) +{ + + /* XXX Unmap the vertex feedback buffers so we can write to them */ + + + if (!stage->draw->feedback.discard) + stage->next->end( stage->next ); +} + + + +static void feedback_reset_stipple_counter( struct draw_stage *stage ) +{ + if (!stage->draw->feedback.discard) + stage->next->reset_stipple_counter( stage->next ); +} + + +/** + * Create feedback drawing stage. + */ +struct draw_stage *draw_feedback_stage( struct draw_context *draw ) +{ + struct feedback_stage *feedback = CALLOC_STRUCT(feedback_stage); + + feedback->stage.draw = draw; + feedback->stage.next = NULL; + feedback->stage.begin = feedback_begin; + feedback->stage.point = feedback_point; + feedback->stage.line = feedback_line; + feedback->stage.tri = feedback_tri; + feedback->stage.end = feedback_end; + feedback->stage.reset_stipple_counter = feedback_reset_stipple_counter; + + return &feedback->stage; +} + + |