From 10f4b37bd70c12c8caaa85ff5b94aec532788abd Mon Sep 17 00:00:00 2001 From: Brian Date: Mon, 9 Jul 2007 16:04:08 -0600 Subject: Rename/move some files to modularize the primitive/draw code. --- src/mesa/pipe/draw/draw_clip.c | 429 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 429 insertions(+) create mode 100644 src/mesa/pipe/draw/draw_clip.c (limited to 'src/mesa/pipe/draw/draw_clip.c') diff --git a/src/mesa/pipe/draw/draw_clip.c b/src/mesa/pipe/draw/draw_clip.c new file mode 100644 index 0000000000..304c43c3f4 --- /dev/null +++ b/src/mesa/pipe/draw/draw_clip.c @@ -0,0 +1,429 @@ +/************************************************************************** + * + * 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 + */ + +#include "imports.h" +#include "macros.h" + +#include "sp_context.h" +#include "sp_prim.h" + +struct clipper { + struct prim_stage stage; + + GLuint active_user_planes; +}; + +/* This is a bit confusing: + */ +static INLINE struct clipper *clipper_stage( struct prim_stage *stage ) +{ + return (struct clipper *)stage; +} + + +#define LINTERP(T, OUT, IN) ((OUT) + (T) * ((IN) - (OUT))) + + +/* All attributes are float[4], so this is easy: + */ +static void interp_attr( GLfloat *fdst, + GLfloat t, + const GLfloat *fin, + const GLfloat *fout ) +{ + fdst[0] = LINTERP( t, fout[0], fin[0] ); + fdst[1] = LINTERP( t, fout[1], fin[1] ); + fdst[2] = LINTERP( t, fout[2], fin[2] ); + fdst[3] = LINTERP( t, fout[3], fin[3] ); +} + + + + +/* Interpolate between two vertices to produce a third. + */ +static void interp( struct clipper *clip, + struct vertex_header *dst, + GLfloat t, + const struct vertex_header *out, + const struct vertex_header *in ) +{ + const GLuint nr_attrs = clip->stage.softpipe->nr_attrs; + GLuint j; + + /* Vertex header. + */ + { + dst->clipmask = 0; + dst->edgeflag = 0; + dst->pad = 0; + } + + /* Clip coordinates: interpolate normally + */ + { + interp_attr(dst->clip, t, in->clip, out->clip); + } + + /* Do the projective divide and insert window coordinates: + */ + { + const GLfloat *pos = dst->clip; + const GLfloat *scale = clip->stage.softpipe->viewport.scale; + const GLfloat *trans = clip->stage.softpipe->viewport.translate; + GLfloat oow; + + oow = 1.0 / pos[3]; + + dst->data[0][0] = pos[0] * oow * scale[0] + trans[0]; + dst->data[0][1] = pos[1] * oow * scale[1] + trans[1]; + dst->data[0][2] = pos[2] * oow * scale[2] + trans[2]; + dst->data[0][3] = oow; + } + + + /* Other attributes + */ + for (j = 1; j < nr_attrs-1; j++) { + interp_attr(dst->data[j], t, in->data[j], out->data[j]); + } +} + + +#define CLIP_USER_BIT 0x40 +#define CLIP_CULL_BIT 0x80 + + +static INLINE GLfloat dot4( const GLfloat *a, + const GLfloat *b ) +{ + GLfloat result = (a[0]*b[0] + + a[1]*b[1] + + a[2]*b[2] + + a[3]*b[3]); + + return result; +} + + +#if 0 +static INLINE void do_tri( struct prim_stage *next, + struct prim_header *header ) +{ + GLuint i; + for (i = 0; i < 3; i++) { + GLfloat *ndc = header->v[i]->data[0]; + _mesa_printf("ndc %f %f %f\n", ndc[0], ndc[1], ndc[2]); + assert(ndc[0] >= -1 && ndc[0] <= 641); + assert(ndc[1] >= 30 && ndc[1] <= 481); + } + _mesa_printf("\n"); + next->tri(next, header); +} +#endif + + +static void emit_poly( struct prim_stage *stage, + struct vertex_header **inlist, + GLuint n ) +{ + struct prim_header header; + GLuint i; + + for (i = 2; i < n; i++) { + header.v[0] = inlist[0]; + header.v[1] = inlist[i-1]; + header.v[2] = inlist[i]; + + { + GLuint tmp0 = header.v[0]->edgeflag; + GLuint tmp2 = header.v[2]->edgeflag; + + if (i != 2) header.v[0]->edgeflag = 0; + if (i != n-1) header.v[2]->edgeflag = 0; + + stage->next->tri( stage->next, &header ); + + header.v[0]->edgeflag = tmp0; + header.v[2]->edgeflag = tmp2; + } + } +} + + +#if 0 +static void emit_poly( struct prim_stage *stage ) +{ + GLuint i; + + for (i = 2; i < n; i++) { + header->v[0] = inlist[0]; + header->v[1] = inlist[i-1]; + header->v[2] = inlist[i]; + + stage->next->tri( stage->next, header ); + } +} +#endif + + +/* Clip a triangle against the viewport and user clip planes. + */ +static void +do_clip_tri( struct prim_stage *stage, + struct prim_header *header, + GLuint clipmask ) +{ + struct clipper *clipper = clipper_stage( stage ); + struct vertex_header *a[MAX_CLIPPED_VERTICES]; + struct vertex_header *b[MAX_CLIPPED_VERTICES]; + struct vertex_header **inlist = a; + struct vertex_header **outlist = b; + GLuint tmpnr = 0; + GLuint n = 3; + GLuint i; + + inlist[0] = header->v[0]; + inlist[1] = header->v[1]; + inlist[2] = header->v[2]; + + /* XXX: Note stupid hack to deal with tnl's 8-bit clipmask. Remove + * this once we correctly use 16bit masks for userclip planes. + */ + clipmask &= ~CLIP_CULL_BIT; + if (clipmask & CLIP_USER_BIT) { + clipmask &= ~CLIP_USER_BIT; + clipmask |= clipper->active_user_planes; + } + + while (clipmask && n >= 3) { + GLuint plane_idx = ffs(clipmask)-1; + const GLfloat *plane = clipper->stage.softpipe->plane[plane_idx]; + struct vertex_header *vert_prev = inlist[0]; + GLfloat dp_prev = dot4( vert_prev->clip, plane ); + GLuint outcount = 0; + + clipmask &= ~(1<clip, plane ); + + if (!IS_NEGATIVE(dp_prev)) { + outlist[outcount++] = vert_prev; + } + + if (DIFFERENT_SIGNS(dp, dp_prev)) { + struct vertex_header *new_vert = clipper->stage.tmp[tmpnr++]; + outlist[outcount++] = new_vert; + + if (IS_NEGATIVE(dp)) { + /* Going out of bounds. Avoid division by zero as we + * know dp != dp_prev from DIFFERENT_SIGNS, above. + */ + GLfloat t = dp / (dp - dp_prev); + interp( clipper, new_vert, t, vert, vert_prev ); + + /* Force edgeflag true in this case: + */ + new_vert->edgeflag = 1; + } else { + /* Coming back in. + */ + GLfloat t = dp_prev / (dp_prev - dp); + interp( clipper, new_vert, t, vert_prev, vert ); + + /* Copy starting vert's edgeflag: + */ + new_vert->edgeflag = vert_prev->edgeflag; + } + } + + vert_prev = vert; + dp_prev = dp; + } + + { + struct vertex_header **tmp = inlist; + inlist = outlist; + outlist = tmp; + n = outcount; + } + } + + /* Emit the polygon as triangles to the setup stage: + */ + if (n >= 3) + emit_poly( stage, inlist, n ); +} + + +/* Clip a line against the viewport and user clip planes. + */ +static void +do_clip_line( struct prim_stage *stage, + struct prim_header *header, + GLuint clipmask ) +{ + struct clipper *clipper = clipper_stage( stage ); + struct vertex_header *v0 = header->v[0]; + struct vertex_header *v1 = header->v[1]; + const GLfloat *pos0 = v0->clip; + const GLfloat *pos1 = v1->clip; + GLfloat t0 = 0; + GLfloat t1 = 0; + + /* XXX: Note stupid hack to deal with tnl's 8-bit clipmask. Remove + * this once we correctly use 16bit masks for userclip planes. + */ + clipmask &= ~CLIP_CULL_BIT; + if (clipmask & CLIP_USER_BIT) { + clipmask &= ~CLIP_USER_BIT; + clipmask |= clipper->active_user_planes; + } + + while (clipmask) { + GLuint plane_idx = ffs(clipmask)-1; + const GLfloat *plane = clipper->stage.softpipe->plane[plane_idx]; + + clipmask &= ~(1< t1) t1 = t; + } + + if (dp0 < 0) { + GLfloat t = dp0 / (dp0 - dp1); + if (t > t0) t0 = t; + } + + if (t0 + t1 >= 1.0) + return; /* discard */ + } + + if (v0->clipmask) { + interp( clipper, stage->tmp[0], t0, v0, v1 ); + header->v[0] = stage->tmp[0]; + } + + if (v1->clipmask) { + interp( clipper, stage->tmp[1], t1, v1, v0 ); + header->v[1] = stage->tmp[1]; + } + + stage->next->line( stage->next, header ); +} + + + +static void clip_begin( struct prim_stage *stage ) +{ + struct clipper *clipper = clipper_stage(stage); + GLuint nr = stage->softpipe->nr_planes; + + /* Hacky bitmask to use when we hit CLIP_USER_BIT: + */ + clipper->active_user_planes = ((1<next->begin( stage->next ); +} + +static void +clip_point( struct prim_stage *stage, + struct prim_header *header ) +{ + if (header->v[0]->clipmask == 0) + stage->next->point( stage->next, header ); +} + + +static void +clip_line( struct prim_stage *stage, + struct prim_header *header ) +{ + GLuint clipmask = (header->v[0]->clipmask | + header->v[1]->clipmask); + + if (clipmask == 0) { + stage->next->line( stage->next, header ); + } + else if ((header->v[0]->clipmask & + header->v[1]->clipmask) == 0) { + do_clip_line(stage, header, clipmask); + } +} + + +static void +clip_tri( struct prim_stage *stage, + struct prim_header *header ) +{ + GLuint clipmask = (header->v[0]->clipmask | + header->v[1]->clipmask | + header->v[2]->clipmask); + + if (clipmask == 0) { + 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); + } +} + +static void clip_end( struct prim_stage *stage ) +{ + stage->next->end( stage->next ); +} + + +struct prim_stage *prim_clip( struct softpipe_context *softpipe ) +{ + struct clipper *clipper = CALLOC_STRUCT(clipper); + + prim_alloc_tmps( &clipper->stage, MAX_CLIPPED_VERTICES ); + + clipper->stage.softpipe = softpipe; + clipper->stage.begin = clip_begin; + clipper->stage.point = clip_point; + clipper->stage.line = clip_line; + clipper->stage.tri = clip_tri; + clipper->stage.end = clip_end; + + return &clipper->stage; +} -- cgit v1.2.3