/************************************************************************** * * 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. * **************************************************************************/ /* * Functions for specifying the post-transformation vertex layout. * * Author: * Brian Paul * Keith Whitwell */ #include "pipe/p_defines.h" #include "pipe/p_context.h" #include "pipe/p_winsys.h" #include "pipe/p_util.h" #include "pipe/draw/draw_private.h" #include "pipe/draw/draw_context.h" #include "pipe/draw/draw_vertex.h" static INLINE void emit_vertex_attr(struct vertex_info *vinfo, attrib_format format, interp_mode interp) { const uint n = vinfo->num_attribs; vinfo->interp_mode[n] = interp; vinfo->format[n] = format; vinfo->num_attribs++; } /** * Compute the size of a vertex, in dwords/floats, to update the * vinfo->size field. */ void draw_compute_vertex_size(struct vertex_info *vinfo) { uint i; vinfo->size = 0; for (i = 0; i < vinfo->num_attribs; i++) { switch (vinfo->format[i]) { case FORMAT_OMIT: break; case FORMAT_4UB: /* fall-through */ case FORMAT_1F: vinfo->size += 1; break; case FORMAT_2F: vinfo->size += 2; break; case FORMAT_3F: vinfo->size += 3; break; case FORMAT_4F: case FORMAT_4F_VIEWPORT: vinfo->size += 4; break; default: assert(0); } } } /** * Tell the drawing module about the layout of post-transformation vertices */ void draw_set_vertex_attributes( struct draw_context *draw, const uint *slot_to_vf_attr, const interp_mode *interps, unsigned nr_attrs ) { struct vertex_info *vinfo = &draw->vertex_info; unsigned i; #if 0 assert(slot_to_vf_attr[0] == TGSI_ATTRIB_POS); #endif memset(vinfo, 0, sizeof(*vinfo)); /* * First three attribs are always the same: header, clip pos, winpos */ emit_vertex_attr(vinfo, FORMAT_1F, INTERP_NONE); emit_vertex_attr(vinfo, FORMAT_4F, INTERP_LINEAR); emit_vertex_attr(vinfo, FORMAT_4F_VIEWPORT, INTERP_LINEAR); /* * Remaining attribs (color, texcoords, etc) */ for (i = 1; i < nr_attrs; i++) { emit_vertex_attr(vinfo, FORMAT_4F, interps[i]); } draw_compute_vertex_size(vinfo); } /** * This function is used to tell the draw module about attributes * (like colors) that need to be selected based on front/back face * orientation. * * The logic is: * if (polygon is back-facing) { * vertex->attrib[front0] = vertex->attrib[back0]; * vertex->attrib[front1] = vertex->attrib[back1]; * } * * \param front0 first attrib to replace if the polygon is back-facing * \param back0 first attrib to copy if the polygon is back-facing * \param front1 second attrib to replace if the polygon is back-facing * \param back1 second attrib to copy if the polygon is back-facing * * Pass -1 to disable two-sided attributes. */ void draw_set_twoside_attributes(struct draw_context *draw, uint front0, uint back0, uint front1, uint back1) { /* XXX we could alternately pass an array of front/back attribs if there's * ever need for more than two. One could imagine a shader extension * that allows arbitrary attributes to be selected based on polygon * orientation... */ draw->attrib_front0 = front0; draw->attrib_back0 = back0; draw->attrib_front1 = front1; draw->attrib_back1 = back1; }