mirror of
https://github.com/KolibriOS/kolibrios.git
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edb28b33f3
git-svn-id: svn://kolibrios.org@3770 a494cfbc-eb01-0410-851d-a64ba20cac60
778 lines
23 KiB
C
778 lines
23 KiB
C
/**************************************************************************
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*
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* Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
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* All Rights Reserved.
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*
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* Permission is hereby granted, free of charge, to any person obtaining a
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* copy of this software and associated documentation files (the
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* "Software"), to deal in the Software without restriction, including
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* without limitation the rights to use, copy, modify, merge, publish,
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* distribute, sub license, and/or sell copies of the Software, and to
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* permit persons to whom the Software is furnished to do so, subject to
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* the following conditions:
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*
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* The above copyright notice and this permission notice (including the
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* next paragraph) shall be included in all copies or substantial portions
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* of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
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* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
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* IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
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* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
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* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
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* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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*
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**************************************************************************/
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/**
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* \brief Clipping stage
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*
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* \author Keith Whitwell <keith@tungstengraphics.com>
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*/
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#include "util/u_memory.h"
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#include "util/u_math.h"
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#include "pipe/p_shader_tokens.h"
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#include "draw_vs.h"
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#include "draw_pipe.h"
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#include "draw_fs.h"
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#include "draw_gs.h"
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/** Set to 1 to enable printing of coords before/after clipping */
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#define DEBUG_CLIP 0
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#ifndef IS_NEGATIVE
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#define IS_NEGATIVE(X) ((X) < 0.0)
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#endif
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#ifndef DIFFERENT_SIGNS
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#define DIFFERENT_SIGNS(x, y) ((x) * (y) <= 0.0F && (x) - (y) != 0.0F)
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#endif
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#define MAX_CLIPPED_VERTICES ((2 * (6 + PIPE_MAX_CLIP_PLANES))+1)
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struct clip_stage {
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struct draw_stage stage; /**< base class */
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/* List of the attributes to be flatshaded. */
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uint num_flat_attribs;
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uint flat_attribs[PIPE_MAX_SHADER_OUTPUTS];
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/* Mask of attributes in noperspective mode */
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boolean noperspective_attribs[PIPE_MAX_SHADER_OUTPUTS];
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float (*plane)[4];
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};
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/** Cast wrapper */
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static INLINE struct clip_stage *clip_stage( struct draw_stage *stage )
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{
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return (struct clip_stage *)stage;
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}
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static INLINE unsigned
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draw_viewport_index(struct draw_context *draw,
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const struct vertex_header *leading_vertex)
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{
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if (draw_current_shader_uses_viewport_index(draw)) {
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unsigned viewport_index_output =
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draw_current_shader_viewport_index_output(draw);
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unsigned viewport_index =
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*((unsigned*)leading_vertex->data[viewport_index_output]);
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return draw_clamp_viewport_idx(viewport_index);
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} else {
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return 0;
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}
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}
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#define LINTERP(T, OUT, IN) ((OUT) + (T) * ((IN) - (OUT)))
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/* All attributes are float[4], so this is easy:
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*/
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static void interp_attr( float dst[4],
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float t,
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const float in[4],
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const float out[4] )
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{
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dst[0] = LINTERP( t, out[0], in[0] );
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dst[1] = LINTERP( t, out[1], in[1] );
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dst[2] = LINTERP( t, out[2], in[2] );
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dst[3] = LINTERP( t, out[3], in[3] );
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}
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/**
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* Copy flat shaded attributes src vertex to dst vertex.
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*/
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static void copy_flat( struct draw_stage *stage,
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struct vertex_header *dst,
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const struct vertex_header *src )
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{
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const struct clip_stage *clipper = clip_stage(stage);
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uint i;
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for (i = 0; i < clipper->num_flat_attribs; i++) {
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const uint attr = clipper->flat_attribs[i];
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COPY_4FV(dst->data[attr], src->data[attr]);
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}
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}
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/* Interpolate between two vertices to produce a third.
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*/
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static void interp( const struct clip_stage *clip,
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struct vertex_header *dst,
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float t,
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const struct vertex_header *out,
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const struct vertex_header *in,
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unsigned viewport_index )
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{
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const unsigned nr_attrs = draw_current_shader_outputs(clip->stage.draw);
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const unsigned pos_attr = draw_current_shader_position_output(clip->stage.draw);
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const unsigned clip_attr = draw_current_shader_clipvertex_output(clip->stage.draw);
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unsigned j;
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float t_nopersp;
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/* Vertex header.
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*/
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dst->clipmask = 0;
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dst->edgeflag = 0; /* will get overwritten later */
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dst->have_clipdist = in->have_clipdist;
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dst->vertex_id = UNDEFINED_VERTEX_ID;
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/* Interpolate the clip-space coords.
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*/
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interp_attr(dst->clip, t, in->clip, out->clip);
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/* interpolate the clip-space position */
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interp_attr(dst->pre_clip_pos, t, in->pre_clip_pos, out->pre_clip_pos);
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/* Do the projective divide and viewport transformation to get
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* new window coordinates:
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*/
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{
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const float *pos = dst->pre_clip_pos;
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const float *scale =
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clip->stage.draw->viewports[viewport_index].scale;
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const float *trans =
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clip->stage.draw->viewports[viewport_index].translate;
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const float oow = 1.0f / pos[3];
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dst->data[pos_attr][0] = pos[0] * oow * scale[0] + trans[0];
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dst->data[pos_attr][1] = pos[1] * oow * scale[1] + trans[1];
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dst->data[pos_attr][2] = pos[2] * oow * scale[2] + trans[2];
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dst->data[pos_attr][3] = oow;
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}
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/**
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* Compute the t in screen-space instead of 3d space to use
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* for noperspective interpolation.
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*
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* The points can be aligned with the X axis, so in that case try
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* the Y. When both points are at the same screen position, we can
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* pick whatever value (the interpolated point won't be in front
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* anyway), so just use the 3d t.
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*/
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{
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int k;
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t_nopersp = t;
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/* find either in.x != out.x or in.y != out.y */
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for (k = 0; k < 2; k++) {
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if (in->clip[k] != out->clip[k]) {
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/* do divide by W, then compute linear interpolation factor */
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float in_coord = in->clip[k] / in->clip[3];
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float out_coord = out->clip[k] / out->clip[3];
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float dst_coord = dst->clip[k] / dst->clip[3];
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t_nopersp = (dst_coord - out_coord) / (in_coord - out_coord);
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break;
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}
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}
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}
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/* Other attributes
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*/
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for (j = 0; j < nr_attrs; j++) {
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if (j != pos_attr && j != clip_attr) {
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if (clip->noperspective_attribs[j])
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interp_attr(dst->data[j], t_nopersp, in->data[j], out->data[j]);
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else
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interp_attr(dst->data[j], t, in->data[j], out->data[j]);
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}
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}
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}
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/**
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* Emit a post-clip polygon to the next pipeline stage. The polygon
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* will be convex and the provoking vertex will always be vertex[0].
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*/
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static void emit_poly( struct draw_stage *stage,
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struct vertex_header **inlist,
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const boolean *edgeflags,
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unsigned n,
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const struct prim_header *origPrim)
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{
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struct prim_header header;
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unsigned i;
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ushort edge_first, edge_middle, edge_last;
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if (stage->draw->rasterizer->flatshade_first) {
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edge_first = DRAW_PIPE_EDGE_FLAG_0;
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edge_middle = DRAW_PIPE_EDGE_FLAG_1;
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edge_last = DRAW_PIPE_EDGE_FLAG_2;
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}
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else {
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edge_first = DRAW_PIPE_EDGE_FLAG_2;
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edge_middle = DRAW_PIPE_EDGE_FLAG_0;
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edge_last = DRAW_PIPE_EDGE_FLAG_1;
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}
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if (!edgeflags[0])
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edge_first = 0;
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/* later stages may need the determinant, but only the sign matters */
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header.det = origPrim->det;
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header.flags = DRAW_PIPE_RESET_STIPPLE | edge_first | edge_middle;
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header.pad = 0;
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for (i = 2; i < n; i++, header.flags = edge_middle) {
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/* order the triangle verts to respect the provoking vertex mode */
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if (stage->draw->rasterizer->flatshade_first) {
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header.v[0] = inlist[0]; /* the provoking vertex */
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header.v[1] = inlist[i-1];
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header.v[2] = inlist[i];
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}
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else {
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header.v[0] = inlist[i-1];
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header.v[1] = inlist[i];
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header.v[2] = inlist[0]; /* the provoking vertex */
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}
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if (!edgeflags[i-1]) {
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header.flags &= ~edge_middle;
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}
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if (i == n - 1 && edgeflags[i])
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header.flags |= edge_last;
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if (DEBUG_CLIP) {
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const struct draw_vertex_shader *vs = stage->draw->vs.vertex_shader;
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uint j, k;
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debug_printf("Clipped tri: (flat-shade-first = %d)\n",
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stage->draw->rasterizer->flatshade_first);
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for (j = 0; j < 3; j++) {
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debug_printf(" Vert %d: clip: %f %f %f %f\n", j,
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header.v[j]->clip[0],
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header.v[j]->clip[1],
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header.v[j]->clip[2],
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header.v[j]->clip[3]);
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for (k = 0; k < vs->info.num_outputs; k++) {
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debug_printf(" Vert %d: Attr %d: %f %f %f %f\n", j, k,
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header.v[j]->data[k][0],
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header.v[j]->data[k][1],
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header.v[j]->data[k][2],
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header.v[j]->data[k][3]);
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}
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}
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}
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stage->next->tri( stage->next, &header );
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}
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}
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static INLINE float
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dot4(const float *a, const float *b)
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{
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return (a[0] * b[0] +
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a[1] * b[1] +
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a[2] * b[2] +
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a[3] * b[3]);
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}
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/*
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* this function extracts the clip distance for the current plane,
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* it first checks if the shader provided a clip distance, otherwise
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* it works out the value using the clipvertex
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*/
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static INLINE float getclipdist(const struct clip_stage *clipper,
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struct vertex_header *vert,
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int plane_idx)
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{
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const float *plane;
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float dp;
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if (vert->have_clipdist && plane_idx >= 6) {
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/* pick the correct clipdistance element from the output vectors */
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int _idx = plane_idx - 6;
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int cdi = _idx >= 4;
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int vidx = cdi ? _idx - 4 : _idx;
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dp = vert->data[draw_current_shader_clipdistance_output(clipper->stage.draw, cdi)][vidx];
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} else {
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plane = clipper->plane[plane_idx];
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dp = dot4(vert->clip, plane);
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}
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return dp;
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}
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/* Clip a triangle against the viewport and user clip planes.
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*/
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static void
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do_clip_tri( struct draw_stage *stage,
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struct prim_header *header,
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unsigned clipmask )
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{
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struct clip_stage *clipper = clip_stage( stage );
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struct vertex_header *a[MAX_CLIPPED_VERTICES];
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struct vertex_header *b[MAX_CLIPPED_VERTICES];
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struct vertex_header **inlist = a;
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struct vertex_header **outlist = b;
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unsigned tmpnr = 0;
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unsigned n = 3;
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unsigned i;
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boolean aEdges[MAX_CLIPPED_VERTICES];
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boolean bEdges[MAX_CLIPPED_VERTICES];
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boolean *inEdges = aEdges;
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boolean *outEdges = bEdges;
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int viewport_index = 0;
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inlist[0] = header->v[0];
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inlist[1] = header->v[1];
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inlist[2] = header->v[2];
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viewport_index = draw_viewport_index(clipper->stage.draw, inlist[0]);
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if (DEBUG_CLIP) {
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const float *v0 = header->v[0]->clip;
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const float *v1 = header->v[1]->clip;
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const float *v2 = header->v[2]->clip;
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debug_printf("Clip triangle:\n");
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debug_printf(" %f, %f, %f, %f\n", v0[0], v0[1], v0[2], v0[3]);
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debug_printf(" %f, %f, %f, %f\n", v1[0], v1[1], v1[2], v1[3]);
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debug_printf(" %f, %f, %f, %f\n", v2[0], v2[1], v2[2], v2[3]);
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}
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/*
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* Note: at this point we can't just use the per-vertex edge flags.
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* We have to observe the edge flag bits set in header->flags which
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* were set during primitive decomposition. Put those flags into
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* an edge flags array which parallels the vertex array.
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* Later, in the 'unfilled' pipeline stage we'll draw the edge if both
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* the header.flags bit is set AND the per-vertex edgeflag field is set.
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*/
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inEdges[0] = !!(header->flags & DRAW_PIPE_EDGE_FLAG_0);
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inEdges[1] = !!(header->flags & DRAW_PIPE_EDGE_FLAG_1);
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inEdges[2] = !!(header->flags & DRAW_PIPE_EDGE_FLAG_2);
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while (clipmask && n >= 3) {
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const unsigned plane_idx = ffs(clipmask)-1;
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const boolean is_user_clip_plane = plane_idx >= 6;
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struct vertex_header *vert_prev = inlist[0];
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boolean *edge_prev = &inEdges[0];
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float dp_prev;
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unsigned outcount = 0;
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dp_prev = getclipdist(clipper, vert_prev, plane_idx);
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clipmask &= ~(1<<plane_idx);
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assert(n < MAX_CLIPPED_VERTICES);
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if (n >= MAX_CLIPPED_VERTICES)
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return;
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inlist[n] = inlist[0]; /* prevent rotation of vertices */
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inEdges[n] = inEdges[0];
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for (i = 1; i <= n; i++) {
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struct vertex_header *vert = inlist[i];
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boolean *edge = &inEdges[i];
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float dp = getclipdist(clipper, vert, plane_idx);
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if (!IS_NEGATIVE(dp_prev)) {
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assert(outcount < MAX_CLIPPED_VERTICES);
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if (outcount >= MAX_CLIPPED_VERTICES)
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return;
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outEdges[outcount] = *edge_prev;
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outlist[outcount++] = vert_prev;
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}
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if (DIFFERENT_SIGNS(dp, dp_prev)) {
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struct vertex_header *new_vert;
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boolean *new_edge;
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assert(tmpnr < MAX_CLIPPED_VERTICES + 1);
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if (tmpnr >= MAX_CLIPPED_VERTICES + 1)
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return;
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new_vert = clipper->stage.tmp[tmpnr++];
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assert(outcount < MAX_CLIPPED_VERTICES);
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if (outcount >= MAX_CLIPPED_VERTICES)
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return;
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new_edge = &outEdges[outcount];
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outlist[outcount++] = new_vert;
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if (IS_NEGATIVE(dp)) {
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/* Going out of bounds. Avoid division by zero as we
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* know dp != dp_prev from DIFFERENT_SIGNS, above.
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*/
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float t = dp / (dp - dp_prev);
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interp( clipper, new_vert, t, vert, vert_prev, viewport_index );
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/* Whether or not to set edge flag for the new vert depends
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* on whether it's a user-defined clipping plane. We're
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* copying NVIDIA's behaviour here.
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*/
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if (is_user_clip_plane) {
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/* we want to see an edge along the clip plane */
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*new_edge = TRUE;
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new_vert->edgeflag = TRUE;
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}
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else {
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/* we don't want to see an edge along the frustum clip plane */
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*new_edge = *edge_prev;
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new_vert->edgeflag = FALSE;
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}
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}
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else {
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/* Coming back in.
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*/
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float t = dp_prev / (dp_prev - dp);
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interp( clipper, new_vert, t, vert_prev, vert, viewport_index );
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/* Copy starting vert's edgeflag:
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*/
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new_vert->edgeflag = vert_prev->edgeflag;
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*new_edge = *edge_prev;
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}
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}
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vert_prev = vert;
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edge_prev = edge;
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dp_prev = dp;
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}
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/* swap in/out lists */
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{
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struct vertex_header **tmp = inlist;
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inlist = outlist;
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outlist = tmp;
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n = outcount;
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}
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{
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boolean *tmp = inEdges;
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inEdges = outEdges;
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outEdges = tmp;
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}
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}
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/* If flat-shading, copy provoking vertex color to polygon vertex[0]
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*/
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if (n >= 3) {
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if (clipper->num_flat_attribs) {
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if (stage->draw->rasterizer->flatshade_first) {
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if (inlist[0] != header->v[0]) {
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assert(tmpnr < MAX_CLIPPED_VERTICES + 1);
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if (tmpnr >= MAX_CLIPPED_VERTICES + 1)
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return;
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inlist[0] = dup_vert(stage, inlist[0], tmpnr++);
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copy_flat(stage, inlist[0], header->v[0]);
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}
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}
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else {
|
|
if (inlist[0] != header->v[2]) {
|
|
assert(tmpnr < MAX_CLIPPED_VERTICES + 1);
|
|
if (tmpnr >= MAX_CLIPPED_VERTICES + 1)
|
|
return;
|
|
inlist[0] = dup_vert(stage, inlist[0], tmpnr++);
|
|
copy_flat(stage, inlist[0], header->v[2]);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Emit the polygon as triangles to the setup stage:
|
|
*/
|
|
emit_poly( stage, inlist, inEdges, n, header );
|
|
}
|
|
}
|
|
|
|
|
|
/* Clip a line against the viewport and user clip planes.
|
|
*/
|
|
static void
|
|
do_clip_line( struct draw_stage *stage,
|
|
struct prim_header *header,
|
|
unsigned clipmask )
|
|
{
|
|
const struct clip_stage *clipper = clip_stage( stage );
|
|
struct vertex_header *v0 = header->v[0];
|
|
struct vertex_header *v1 = header->v[1];
|
|
float t0 = 0.0F;
|
|
float t1 = 0.0F;
|
|
struct prim_header newprim;
|
|
int viewport_index = draw_viewport_index(clipper->stage.draw, v0);
|
|
|
|
while (clipmask) {
|
|
const unsigned plane_idx = ffs(clipmask)-1;
|
|
const float dp0 = getclipdist(clipper, v0, plane_idx);
|
|
const float dp1 = getclipdist(clipper, v1, plane_idx);
|
|
|
|
if (dp1 < 0.0F) {
|
|
float t = dp1 / (dp1 - dp0);
|
|
t1 = MAX2(t1, t);
|
|
}
|
|
|
|
if (dp0 < 0.0F) {
|
|
float t = dp0 / (dp0 - dp1);
|
|
t0 = MAX2(t0, t);
|
|
}
|
|
|
|
if (t0 + t1 >= 1.0F)
|
|
return; /* discard */
|
|
|
|
clipmask &= ~(1 << plane_idx); /* turn off this plane's bit */
|
|
}
|
|
|
|
if (v0->clipmask) {
|
|
interp( clipper, stage->tmp[0], t0, v0, v1, viewport_index );
|
|
copy_flat(stage, stage->tmp[0], v0);
|
|
newprim.v[0] = stage->tmp[0];
|
|
}
|
|
else {
|
|
newprim.v[0] = v0;
|
|
}
|
|
|
|
if (v1->clipmask) {
|
|
interp( clipper, stage->tmp[1], t1, v1, v0, viewport_index );
|
|
newprim.v[1] = stage->tmp[1];
|
|
}
|
|
else {
|
|
newprim.v[1] = v1;
|
|
}
|
|
|
|
stage->next->line( stage->next, &newprim );
|
|
}
|
|
|
|
|
|
static void
|
|
clip_point( struct draw_stage *stage,
|
|
struct prim_header *header )
|
|
{
|
|
if (header->v[0]->clipmask == 0)
|
|
stage->next->point( stage->next, header );
|
|
}
|
|
|
|
|
|
static void
|
|
clip_line( struct draw_stage *stage,
|
|
struct prim_header *header )
|
|
{
|
|
unsigned clipmask = (header->v[0]->clipmask |
|
|
header->v[1]->clipmask);
|
|
|
|
if (clipmask == 0) {
|
|
/* no clipping needed */
|
|
stage->next->line( stage->next, header );
|
|
}
|
|
else if ((header->v[0]->clipmask &
|
|
header->v[1]->clipmask) == 0) {
|
|
do_clip_line(stage, header, clipmask);
|
|
}
|
|
/* else, totally clipped */
|
|
}
|
|
|
|
|
|
static void
|
|
clip_tri( struct draw_stage *stage,
|
|
struct prim_header *header )
|
|
{
|
|
unsigned clipmask = (header->v[0]->clipmask |
|
|
header->v[1]->clipmask |
|
|
header->v[2]->clipmask);
|
|
|
|
if (clipmask == 0) {
|
|
/* no clipping needed */
|
|
stage->next->tri( stage->next, header );
|
|
}
|
|
else if ((header->v[0]->clipmask &
|
|
header->v[1]->clipmask &
|
|
header->v[2]->clipmask) == 0) {
|
|
do_clip_tri(stage, header, clipmask);
|
|
}
|
|
}
|
|
|
|
|
|
/* Update state. Could further delay this until we hit the first
|
|
* primitive that really requires clipping.
|
|
*/
|
|
static void
|
|
clip_init_state( struct draw_stage *stage )
|
|
{
|
|
struct clip_stage *clipper = clip_stage( stage );
|
|
const struct draw_vertex_shader *vs = stage->draw->vs.vertex_shader;
|
|
const struct draw_geometry_shader *gs = stage->draw->gs.geometry_shader;
|
|
const struct draw_fragment_shader *fs = stage->draw->fs.fragment_shader;
|
|
uint i;
|
|
const struct tgsi_shader_info *vs_info = gs ? &gs->info : &vs->info;
|
|
|
|
/* We need to know for each attribute what kind of interpolation is
|
|
* done on it (flat, smooth or noperspective). But the information
|
|
* is not directly accessible for outputs, only for inputs. So we
|
|
* have to match semantic name and index between the VS (or GS/ES)
|
|
* outputs and the FS inputs to get to the interpolation mode.
|
|
*
|
|
* The only hitch is with gl_FrontColor/gl_BackColor which map to
|
|
* gl_Color, and their Secondary versions. First there are (up to)
|
|
* two outputs for one input, so we tuck the information in a
|
|
* specific array. Second if they don't have qualifiers, the
|
|
* default value has to be picked from the global shade mode.
|
|
*
|
|
* Of course, if we don't have a fragment shader in the first
|
|
* place, defaults should be used.
|
|
*/
|
|
|
|
/* First pick up the interpolation mode for
|
|
* gl_Color/gl_SecondaryColor, with the correct default.
|
|
*/
|
|
int indexed_interp[2];
|
|
indexed_interp[0] = indexed_interp[1] = stage->draw->rasterizer->flatshade ?
|
|
TGSI_INTERPOLATE_CONSTANT : TGSI_INTERPOLATE_PERSPECTIVE;
|
|
|
|
if (fs) {
|
|
for (i = 0; i < fs->info.num_inputs; i++) {
|
|
if (fs->info.input_semantic_name[i] == TGSI_SEMANTIC_COLOR) {
|
|
if (fs->info.input_interpolate[i] != TGSI_INTERPOLATE_COLOR)
|
|
indexed_interp[fs->info.input_semantic_index[i]] = fs->info.input_interpolate[i];
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Then resolve the interpolation mode for every output attribute.
|
|
*
|
|
* Given how the rest of the code, the most efficient way is to
|
|
* have a vector of flat-mode attributes, and a mask for
|
|
* noperspective attributes.
|
|
*/
|
|
|
|
clipper->num_flat_attribs = 0;
|
|
memset(clipper->noperspective_attribs, 0, sizeof(clipper->noperspective_attribs));
|
|
for (i = 0; i < vs_info->num_outputs; i++) {
|
|
/* Find the interpolation mode for a specific attribute
|
|
*/
|
|
int interp;
|
|
|
|
/* If it's gl_{Front,Back}{,Secondary}Color, pick up the mode
|
|
* from the array we've filled before. */
|
|
if (vs_info->output_semantic_name[i] == TGSI_SEMANTIC_COLOR ||
|
|
vs_info->output_semantic_name[i] == TGSI_SEMANTIC_BCOLOR) {
|
|
interp = indexed_interp[vs_info->output_semantic_index[i]];
|
|
} else {
|
|
/* Otherwise, search in the FS inputs, with a decent default
|
|
* if we don't find it.
|
|
*/
|
|
uint j;
|
|
interp = TGSI_INTERPOLATE_PERSPECTIVE;
|
|
if (fs) {
|
|
for (j = 0; j < fs->info.num_inputs; j++) {
|
|
if (vs_info->output_semantic_name[i] == fs->info.input_semantic_name[j] &&
|
|
vs_info->output_semantic_index[i] == fs->info.input_semantic_index[j]) {
|
|
interp = fs->info.input_interpolate[j];
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/* If it's flat, add it to the flat vector. Otherwise update
|
|
* the noperspective mask.
|
|
*/
|
|
if (interp == TGSI_INTERPOLATE_CONSTANT) {
|
|
clipper->flat_attribs[clipper->num_flat_attribs] = i;
|
|
clipper->num_flat_attribs++;
|
|
} else
|
|
clipper->noperspective_attribs[i] = interp == TGSI_INTERPOLATE_LINEAR;
|
|
}
|
|
|
|
stage->tri = clip_tri;
|
|
stage->line = clip_line;
|
|
}
|
|
|
|
|
|
|
|
static void clip_first_tri( struct draw_stage *stage,
|
|
struct prim_header *header )
|
|
{
|
|
clip_init_state( stage );
|
|
stage->tri( stage, header );
|
|
}
|
|
|
|
static void clip_first_line( struct draw_stage *stage,
|
|
struct prim_header *header )
|
|
{
|
|
clip_init_state( stage );
|
|
stage->line( stage, header );
|
|
}
|
|
|
|
|
|
static void clip_flush( struct draw_stage *stage,
|
|
unsigned flags )
|
|
{
|
|
stage->tri = clip_first_tri;
|
|
stage->line = clip_first_line;
|
|
stage->next->flush( stage->next, flags );
|
|
}
|
|
|
|
|
|
static void clip_reset_stipple_counter( struct draw_stage *stage )
|
|
{
|
|
stage->next->reset_stipple_counter( stage->next );
|
|
}
|
|
|
|
|
|
static void clip_destroy( struct draw_stage *stage )
|
|
{
|
|
draw_free_temp_verts( stage );
|
|
FREE( stage );
|
|
}
|
|
|
|
|
|
/**
|
|
* Allocate a new clipper stage.
|
|
* \return pointer to new stage object
|
|
*/
|
|
struct draw_stage *draw_clip_stage( struct draw_context *draw )
|
|
{
|
|
struct clip_stage *clipper = CALLOC_STRUCT(clip_stage);
|
|
if (clipper == NULL)
|
|
goto fail;
|
|
|
|
clipper->stage.draw = draw;
|
|
clipper->stage.name = "clipper";
|
|
clipper->stage.point = clip_point;
|
|
clipper->stage.line = clip_first_line;
|
|
clipper->stage.tri = clip_first_tri;
|
|
clipper->stage.flush = clip_flush;
|
|
clipper->stage.reset_stipple_counter = clip_reset_stipple_counter;
|
|
clipper->stage.destroy = clip_destroy;
|
|
|
|
clipper->plane = draw->plane;
|
|
|
|
if (!draw_alloc_temp_verts( &clipper->stage, MAX_CLIPPED_VERTICES+1 ))
|
|
goto fail;
|
|
|
|
return &clipper->stage;
|
|
|
|
fail:
|
|
if (clipper)
|
|
clipper->stage.destroy( &clipper->stage );
|
|
|
|
return NULL;
|
|
}
|