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Diffstat (limited to 'src/gallium/auxiliary/draw/draw_passthrough.c')
| -rw-r--r-- | src/gallium/auxiliary/draw/draw_passthrough.c | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/src/gallium/auxiliary/draw/draw_passthrough.c b/src/gallium/auxiliary/draw/draw_passthrough.c new file mode 100644 index 0000000000..a51fa0ab23 --- /dev/null +++ b/src/gallium/auxiliary/draw/draw_passthrough.c @@ -0,0 +1,222 @@ +/************************************************************************** + * + * 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. + * + **************************************************************************/ + + /* + * Authors: + * Keith Whitwell <keith@tungstengraphics.com> + */ + + +/* This code is a prototype of what a passhthrough vertex shader might + * look like. + * + * Probably the best approach for us is to do: + * - vertex fetch + * - vertex shader + * - cliptest / viewport transform + * + * in one step, then examine the clipOrMask & choose between two paths: + * + * Either: + * - build primitive headers + * - clip and the primitive path + * - build clipped vertex buffers, + * - vertex-emit to vbuf buffers + * + * Or, if no clipping: + * - vertex-emit directly to vbuf buffers + * + * But when bypass clipping is enabled, we just take the latter + * choice. If (some new) passthrough-vertex-shader flag is also set, + * the pipeline degenerates to: + * + * - vertex fetch + * - vertex emit to vbuf buffers + * + * Which is what is prototyped here. + */ +#include "pipe/p_util.h" +#include "draw/draw_context.h" +#include "draw/draw_private.h" +#include "draw/draw_vbuf.h" +#include "draw/draw_vertex.h" + + + +/* Example of a fetch/emit passthrough shader which could be + * generated when bypass_clipping is enabled on a passthrough vertex + * shader. + */ +static void fetch_xyz_rgb_st( struct draw_context *draw, + float *out, + unsigned start, + unsigned count ) +{ + const unsigned *pitch = draw->vertex_fetch.pitch; + const ubyte **src = draw->vertex_fetch.src_ptr; + unsigned i; + + const ubyte *xyzw = src[0] + start * pitch[0]; + const ubyte *rgba = src[1] + start * pitch[1]; + const ubyte *st = src[2] + start * pitch[2]; + + /* loop over vertex attributes (vertex shader inputs) + */ + for (i = 0; i < count; i++) { + { + const float *in = (const float *)xyzw; xyzw += pitch[0]; + /* decode input, encode output. Assume both are float[4] */ + out[0] = in[0]; + out[1] = in[1]; + out[2] = in[2]; + out[3] = in[3]; + } + + { + const float *in = (const float *)rgba; rgba += pitch[1]; + /* decode input, encode output. Assume both are float[4] */ + out[4] = in[0]; + out[5] = in[1]; + out[6] = in[2]; + out[7] = in[3]; + } + + { + const float *in = (const float *)st; st += pitch[2]; + /* decode input, encode output. Assume both are float[2] */ + out[8] = in[0]; + out[9] = in[1]; + } + + out += 10; + } +} + + +static boolean update_shader( struct draw_context *draw ) +{ + const struct vertex_info *vinfo = draw->render->get_vertex_info(draw->render); + + unsigned nr_attrs = vinfo->num_attribs; + unsigned i; + + for (i = 0; i < nr_attrs; i++) { + unsigned buf = draw->vertex_element[i].vertex_buffer_index; + + draw->vertex_fetch.src_ptr[i] = (const ubyte *) draw->user.vbuffer[buf] + + draw->vertex_buffer[buf].buffer_offset + + draw->vertex_element[i].src_offset; + + draw->vertex_fetch.pitch[i] = draw->vertex_buffer[buf].pitch; + draw->vertex_fetch.fetch[i] = NULL; + } + + draw->vertex_fetch.nr_attrs = nr_attrs; + draw->vertex_fetch.fetch_func = NULL; + draw->vertex_fetch.pt_fetch = NULL; + + draw->pt.hw_vertex_size = vinfo->size * 4; + + /* Just trying to figure out how this would work: + */ + if (nr_attrs == 3 && + 0 /* some other tests */) + { + draw->vertex_fetch.pt_fetch = fetch_xyz_rgb_st; + assert(vinfo->size == 10); + return TRUE; + } + + return FALSE; +} + + + +static boolean set_prim( struct draw_context *draw, + unsigned prim ) +{ + assert(!draw->user.elts); + + draw->pt.prim = prim; + + switch (prim) { + case PIPE_PRIM_LINE_LOOP: + case PIPE_PRIM_QUADS: + case PIPE_PRIM_QUAD_STRIP: + return FALSE; + default: + draw->render->set_primitive( draw->render, prim ); + return TRUE; + } +} + + + +boolean +draw_passthrough_arrays(struct draw_context *draw, + unsigned prim, + unsigned start, + unsigned count) +{ + float *hw_verts; + + if (!set_prim(draw, prim)) + return FALSE; + + if (!update_shader( draw )) + return FALSE; + + hw_verts = draw->render->allocate_vertices( draw->render, + draw->pt.hw_vertex_size, + count ); + + if (!hw_verts) + return FALSE; + + /* Single routine to fetch vertices, run shader and emit HW verts. + * Clipping and viewport transformation are done on hardware. + */ + draw->vertex_fetch.pt_fetch( draw, + hw_verts, + start, count ); + + /* Draw arrays path to avoid re-emitting index list again and + * again. + */ + draw->render->draw_arrays( draw->render, + start, + count ); + + + draw->render->release_vertices( draw->render, + hw_verts, + draw->pt.hw_vertex_size, + count ); + + return TRUE; +} + |