676 lines
23 KiB
C
676 lines
23 KiB
C
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/*
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** Copyright 1991, Silicon Graphics, Inc.
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** All Rights Reserved.
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**
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** This is UNPUBLISHED PROPRIETARY SOURCE CODE of Silicon Graphics, Inc.;
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** the contents of this file may not be disclosed to third parties, copied or
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** duplicated in any form, in whole or in part, without the prior written
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** permission of Silicon Graphics, Inc.
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**
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** RESTRICTED RIGHTS LEGEND:
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** Use, duplication or disclosure by the Government is subject to restrictions
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** as set forth in subdivision (c)(1)(ii) of the Rights in Technical Data
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** and Computer Software clause at DFARS 252.227-7013, and/or in similar or
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** successor clauses in the FAR, DOD or NASA FAR Supplement. Unpublished -
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** rights reserved under the Copyright Laws of the United States.
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**
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** $Revision: 1.16 $
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** $Date: 1993/09/23 16:33:23 $
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*/
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#include "precomp.h"
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#pragma hdrstop
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#include <fixed.h>
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/*
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** Clip an input polygon against a clipping plane outputing the new
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** vertex pointers in ov and return the number of them. See the line
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** clipping code for an in depth discussion of how "t" is computed.
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**
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** NOTE: In order to handle non-convex polygons here without dying,
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** we count the number of verticies generated by clipping. If the
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** count ever gets to 3, then it must be a non-convex polygon (because
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** it means the polygon crossed the clipping plane three times, which is
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** impossible for a convex polygon).
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*/
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static GLint clipToPlane(__GLcontext *gc, __GLvertex **iv, GLint niv,
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__GLvertex **ov, GLuint offs, GLboolean negate)
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{
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GLint i, nout, generated;
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__GLvertex *s, *p, *newVertex, *temp;
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__GLfloat pDist, sDist, t;
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PFN_VERTEX_CLIP_PROC clip;
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#ifdef GL_WIN_phong_shading
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GLboolean doNormalize = (gc->state.enables.general &
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__GL_NORMALIZE_ENABLE);
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#endif //GL_WIN_phong_shading
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nout = 0;
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generated = 0;
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temp = gc->transform.nextClipTemp;
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clip = gc->procs.polyClipParam;
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s = iv[niv-1];
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if (negate)
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{
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sDist = s->clip.w - *(__GLfloat *)((GLubyte *)s + offs);
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}
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else
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{
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sDist = *(__GLfloat *)((GLubyte *)s + offs) + s->clip.w;
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}
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for (i = 0; i < niv; i++) {
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p = iv[i];
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if (negate)
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{
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pDist = p->clip.w - *(__GLfloat *)((GLubyte *)p + offs);
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}
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else
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{
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pDist = *(__GLfloat *)((GLubyte *)p + offs) + p->clip.w;
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}
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if (__GL_FLOAT_GEZ(pDist)) {
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/* p is inside the clipping plane half space */
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if (__GL_FLOAT_GEZ(sDist)) {
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/* s is inside the clipping plane half space */
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*ov++ = p;
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nout++;
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} else {
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/* s is outside the clipping plane half space */
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t = pDist / (pDist - sDist);
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newVertex = temp++;
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(*clip)(newVertex, s, p, t);
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#ifdef GL_WIN_phong_shading
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if (doNormalize) __glNormalize(&newVertex->normal.x,
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&newVertex->normal.x);
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#endif //GL_WIN_phong_shading
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#ifndef NT
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// edgeflag is now part of has field.
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newVertex->boundaryEdge = s->boundaryEdge;
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#endif
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newVertex->has = s->has;
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newVertex->clipCode = s->clipCode;
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ASSERTOPENGL(newVertex->color ==
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&newVertex->colors[__GL_FRONTFACE],
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"Vertex color pointer wrong\n");
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*ov++ = newVertex;
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*ov++ = p;
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nout += 2;
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if (++generated >= 3) {
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/* Toss the non-convex polygon */
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return 0;
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}
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}
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} else {
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/* p is outside the clipping plane half space */
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if (__GL_FLOAT_GEZ(sDist)) {
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/*
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** s is inside the clipping plane half space
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**
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** NOTE: To avoid cracking in polygons with shared
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** clipped edges we always compute "t" from the out
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** vertex to the in vertex. The above clipping code gets
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** this for free (p is in and s is out). In this code p
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** is out and s is in, so we reverse the t computation
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** and the argument order to __glDoClip.
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*/
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t = sDist / (sDist - pDist);
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newVertex = temp++;
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(*clip)(newVertex, p, s, t);
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#ifdef GL_WIN_phong_shading
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if (doNormalize) __glNormalize(&newVertex->normal.x,
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&newVertex->normal.x);
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#endif //GL_WIN_phong_shading
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#ifdef NT
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// edgeflag is now part of has field.
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newVertex->has = s->has | __GL_HAS_EDGEFLAG_BOUNDARY;
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newVertex->clipCode = p->clipCode;
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#else
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newVertex->boundaryEdge = GL_TRUE;
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newVertex->has = s->has;
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#endif
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ASSERTOPENGL(newVertex->color ==
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&newVertex->colors[__GL_FRONTFACE],
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"Vertex color pointer wrong\n");
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*ov++ = newVertex;
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nout++;
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if (++generated >= 3) {
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/* Toss the non-convex polygon */
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return 0;
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}
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} else {
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/* both points are outside */
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}
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}
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s = p;
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sDist = pDist;
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}
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gc->transform.nextClipTemp = temp;
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return nout;
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}
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/*
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** Identical to clipToPlane(), except that the clipping is done in eye
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** space.
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*/
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static GLint clipToPlaneEye(__GLcontext *gc, __GLvertex **iv, GLint niv,
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__GLvertex **ov, __GLcoord *plane)
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{
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GLint i, nout, generated;
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__GLvertex *s, *p, *newVertex, *temp;
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__GLfloat pDist, sDist, t;
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PFN_VERTEX_CLIP_PROC clip;
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#ifdef GL_WIN_phong_shading
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GLboolean doNormalize = (gc->state.enables.general &
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__GL_NORMALIZE_ENABLE);
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#endif //GL_WIN_phong_shading
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nout = 0;
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generated = 0;
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temp = gc->transform.nextClipTemp;
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clip = gc->procs.polyClipParam;
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s = iv[niv-1];
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sDist = (((POLYDATA *)s)->eye.x * plane->x) +
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(((POLYDATA *)s)->eye.y * plane->y) +
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(((POLYDATA *)s)->eye.z * plane->z) +
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(((POLYDATA *)s)->eye.w * plane->w);
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for (i = 0; i < niv; i++) {
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p = iv[i];
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pDist = (((POLYDATA *)p)->eye.x * plane->x) +
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(((POLYDATA *)p)->eye.y * plane->y) +
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(((POLYDATA *)p)->eye.z * plane->z) +
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(((POLYDATA *)p)->eye.w * plane->w);
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if (__GL_FLOAT_GEZ(pDist)) {
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/* p is inside the clipping plane half space */
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if (__GL_FLOAT_GEZ(sDist)) {
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/* s is inside the clipping plane half space */
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*ov++ = p;
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nout++;
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} else {
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/* s is outside the clipping plane half space */
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t = pDist / (pDist - sDist);
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newVertex = temp++;
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(*clip)(newVertex, s, p, t);
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#ifdef GL_WIN_phong_shading
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if (doNormalize) __glNormalize(&newVertex->normal.x,
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&newVertex->normal.x);
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#endif //GL_WIN_phong_shading
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((POLYDATA *)newVertex)->eye.x =
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t*(((POLYDATA *)s)->eye.x - ((POLYDATA *)p)->eye.x) +
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((POLYDATA *)p)->eye.x;
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((POLYDATA *)newVertex)->eye.y =
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t*(((POLYDATA *)s)->eye.y - ((POLYDATA *)p)->eye.y) +
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((POLYDATA *)p)->eye.y;
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((POLYDATA *)newVertex)->eye.z =
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t*(((POLYDATA *)s)->eye.z - ((POLYDATA *)p)->eye.z) +
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((POLYDATA *)p)->eye.z;
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((POLYDATA *)newVertex)->eye.w =
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t*(((POLYDATA *)s)->eye.w - ((POLYDATA *)p)->eye.w) +
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((POLYDATA *)p)->eye.w;
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#ifndef NT
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// edgeflag is now part of has field.
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newVertex->boundaryEdge = s->boundaryEdge;
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#endif
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newVertex->has = s->has;
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newVertex->clipCode = s->clipCode;
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ASSERTOPENGL(newVertex->color ==
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&newVertex->colors[__GL_FRONTFACE],
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"Vertex color pointer wrong\n");
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*ov++ = newVertex;
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*ov++ = p;
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nout += 2;
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if (++generated >= 3) {
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/* Toss the non-convex polygon */
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return 0;
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}
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}
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} else {
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/* p is outside the clipping plane half space */
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if (__GL_FLOAT_GEZ(sDist)) {
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/*
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** s is inside the clipping plane half space
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**
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** NOTE: To avoid cracking in polygons with shared
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** clipped edges we always compute "t" from the out
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** vertex to the in vertex. The above clipping code gets
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** this for free (p is in and s is out). In this code p
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** is out and s is in, so we reverse the t computation
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** and the argument order to __glDoClip.
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*/
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t = sDist / (sDist - pDist);
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newVertex = temp++;
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(*clip)(newVertex, p, s, t);
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#ifdef GL_WIN_phong_shading
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if (doNormalize) __glNormalize(&newVertex->normal.x,
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&newVertex->normal.x);
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#endif //GL_WIN_phong_shading
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((POLYDATA *)newVertex)->eye.x =
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t*(((POLYDATA *)p)->eye.x - ((POLYDATA *)s)->eye.x) +
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((POLYDATA *)s)->eye.x;
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((POLYDATA *)newVertex)->eye.y =
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t*(((POLYDATA *)p)->eye.y - ((POLYDATA *)s)->eye.y) +
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((POLYDATA *)s)->eye.y;
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((POLYDATA *)newVertex)->eye.z =
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t*(((POLYDATA *)p)->eye.z - ((POLYDATA *)s)->eye.z) +
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((POLYDATA *)s)->eye.z;
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((POLYDATA *)newVertex)->eye.w =
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t*(((POLYDATA *)p)->eye.w - ((POLYDATA *)s)->eye.w) +
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((POLYDATA *)s)->eye.w;
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#ifdef NT
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// edgeflag is now part of has field.
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newVertex->has = s->has | __GL_HAS_EDGEFLAG_BOUNDARY;
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newVertex->clipCode = p->clipCode;
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#else
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newVertex->boundaryEdge = GL_TRUE;
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newVertex->has = s->has;
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#endif
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ASSERTOPENGL(newVertex->color ==
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&newVertex->colors[__GL_FRONTFACE],
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"Vertex color pointer wrong\n");
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*ov++ = newVertex;
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nout++;
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if (++generated >= 3) {
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/* Toss the non-convex polygon */
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return 0;
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}
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} else {
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/* both points are outside */
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}
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}
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s = p;
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sDist = pDist;
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}
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gc->transform.nextClipTemp = temp;
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return nout;
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}
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/*
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** Each clipping plane can add at most one vertex to a convex polygon (it may
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** remove up to all of the verticies). The clipping will leave a polygon
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** convex. Because of this the maximum number of verticies output from
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** the clipToPlane procedure will be total number of clip planes (assuming
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** each plane adds one new vertex) plus the original number of verticies
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** (3 since this if for triangles).
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*/
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#ifndef __CLIP_FIX
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#define __GL_TOTAL_CLIP_PLANES 20 /*XXX*/
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#ifdef NT
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#define __GL_MAX_CLIP_VERTEX (__GL_TOTAL_CLIP_PLANES + __GL_MAX_POLYGON_CLIP_SIZE)
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#else
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#define __GL_MAX_CLIP_VERTEX (__GL_TOTAL_CLIP_PLANES + __GL_NVBUF)
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#endif
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#endif
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void __glDoPolygonClip(__GLcontext *gc, __GLvertex **iv, GLint nout,
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GLuint allClipCodes)
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{
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#ifndef __CLIP_FIX
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__GLvertex *ov[__GL_TOTAL_CLIP_PLANES][__GL_MAX_CLIP_VERTEX];
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#endif
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__GLvertex **ivp;
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__GLvertex **ovp;
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__GLvertex *p0, *p1, *p2;
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__GLcoord *plane;
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GLint i;
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__GLviewport *vp;
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__GLfloat one, vpXScale, vpYScale, vpZScale;
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__GLfloat vpXCenter, vpYCenter, vpZCenter;
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PFN_RENDER_TRIANGLE rt;
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__GLfloat llx, lly, urx, ury;
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__GLfloat winx, winy;
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GLuint clipCodes;
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// We have to turn rounding on. Otherwise, the fast FP-comparison
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// routines below can fail:
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FPU_SAVE_MODE();
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FPU_ROUND_ON_PREC_HI();
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/*
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** Reset nextClipTemp pointer for any new verticies that are generated
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** during the clipping.
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*/
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gc->transform.nextClipTemp = gc->transform.clipTemp;
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ivp = &iv[0];
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/*
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** Check each of the clipping planes by examining the allClipCodes
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** mask. Note that no bits will be set in allClipCodes for clip
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** planes that are not enabled.
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*/
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if (allClipCodes) {
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/* Now clip against the clipping planes */
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#ifndef __CLIP_FIX
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ovp = &ov[0][0];
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#else
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|
|
ovp = &(((__GLGENcontext *)gc)->pwndLocked->buffers->clip_verts[0][0]);
|
||
|
|
#endif
|
||
|
|
/*
|
||
|
|
** Do user clip planes first, because we will maintain eye coordinates
|
||
|
|
** only while doing user clip planes. They are ignored for the
|
||
|
|
** frustum clipping planes.
|
||
|
|
*/
|
||
|
|
clipCodes = allClipCodes >> 6;
|
||
|
|
if (clipCodes) {
|
||
|
|
plane = &gc->state.transform.eyeClipPlanes[0];
|
||
|
|
do {
|
||
|
|
if (clipCodes & 1) {
|
||
|
|
nout = clipToPlaneEye(gc, ivp, nout, ovp, plane);
|
||
|
|
ASSERTOPENGL(nout <= __GL_MAX_CLIP_VERTEX,
|
||
|
|
"Too many clip vertices\n");
|
||
|
|
if (nout < 3) {
|
||
|
|
FPU_RESTORE_MODE();
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
ivp = ovp;
|
||
|
|
ovp += __GL_MAX_CLIP_VERTEX;
|
||
|
|
}
|
||
|
|
clipCodes >>= 1;
|
||
|
|
plane++;
|
||
|
|
} while (clipCodes);
|
||
|
|
}
|
||
|
|
|
||
|
|
allClipCodes &= __GL_FRUSTUM_CLIP_MASK;
|
||
|
|
if (allClipCodes) {
|
||
|
|
i = 0;
|
||
|
|
do {
|
||
|
|
if (allClipCodes & 1) {
|
||
|
|
nout = clipToPlane(gc, ivp, nout, ovp,
|
||
|
|
__glFrustumOffsets[i],
|
||
|
|
(GLboolean)(i & 1));
|
||
|
|
ASSERTOPENGL(nout <= __GL_MAX_CLIP_VERTEX,
|
||
|
|
"Too many clip vertices\n");
|
||
|
|
if (nout < 3) {
|
||
|
|
FPU_RESTORE_MODE();
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
ivp = ovp;
|
||
|
|
ovp += __GL_MAX_CLIP_VERTEX;
|
||
|
|
}
|
||
|
|
allClipCodes >>= 1;
|
||
|
|
i++;
|
||
|
|
} while (allClipCodes);
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
** Calculate final screen coordinates. Next phase of polygon
|
||
|
|
** processing assumes that window coordinates are already computed.
|
||
|
|
*/
|
||
|
|
vp = &gc->state.viewport;
|
||
|
|
vpXCenter = vp->xCenter;
|
||
|
|
vpYCenter = vp->yCenter;
|
||
|
|
vpZCenter = vp->zCenter;
|
||
|
|
vpXScale = vp->xScale;
|
||
|
|
vpYScale = vp->yScale;
|
||
|
|
vpZScale = vp->zScale;
|
||
|
|
ovp = ivp;
|
||
|
|
one = __glOne;
|
||
|
|
|
||
|
|
llx = vpXCenter - vpXScale;
|
||
|
|
urx = vpXCenter + vpXScale;
|
||
|
|
if (vpYScale > 0) {
|
||
|
|
lly = vpYCenter - vpYScale;
|
||
|
|
ury = vpYCenter + vpYScale;
|
||
|
|
} else {
|
||
|
|
lly = vpYCenter + vpYScale;
|
||
|
|
ury = vpYCenter - vpYScale;
|
||
|
|
}
|
||
|
|
|
||
|
|
for (i = nout; --i >= 0; ) {
|
||
|
|
__GLfloat x, y, z, wInv;
|
||
|
|
|
||
|
|
p0 = *ovp++;
|
||
|
|
|
||
|
|
// If the clipCode is zero then the window coordinates
|
||
|
|
// were computed at the time of clipCode determination
|
||
|
|
// Generated vertices' clipCodes are set to the out vertex
|
||
|
|
// to ensure that their window coords are computed
|
||
|
|
if (p0->clipCode != 0)
|
||
|
|
{
|
||
|
|
#ifdef NT
|
||
|
|
/* XXX (mf) prevent divide-by-zero */
|
||
|
|
if (__GL_FLOAT_EQZ(p0->clip.w))
|
||
|
|
wInv = __glZero;
|
||
|
|
else
|
||
|
|
wInv = one / p0->clip.w;
|
||
|
|
#else
|
||
|
|
wInv = one / p0->clip.w;
|
||
|
|
#endif
|
||
|
|
x = p0->clip.x; y = p0->clip.y; z = p0->clip.z;
|
||
|
|
winx = x * vpXScale * wInv + vpXCenter;
|
||
|
|
winy = y * vpYScale * wInv + vpYCenter;
|
||
|
|
p0->window.z = z * vpZScale * wInv + vpZCenter;
|
||
|
|
p0->window.w = wInv;
|
||
|
|
/*
|
||
|
|
** Check if these window coordinates are legal. At this
|
||
|
|
** point, it is quite possible that they are not. Trivially
|
||
|
|
** pull them into the legal viewport region if necessary.
|
||
|
|
*/
|
||
|
|
if (winx < llx) winx = llx;
|
||
|
|
else if (winx > urx) winx = urx;
|
||
|
|
if (winy < lly) winy = lly;
|
||
|
|
else if (winy > ury) winy = ury;
|
||
|
|
p0->window.x = winx;
|
||
|
|
p0->window.y = winy;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// Restore mode before rendering
|
||
|
|
FPU_RESTORE_MODE();
|
||
|
|
|
||
|
|
#if 0 //def GL_WIN_phong_shading
|
||
|
|
if (gc->state.light.shadingModel == GL_PHONG_EXT)
|
||
|
|
{
|
||
|
|
__GLvertex *minv;
|
||
|
|
__GLvertex **cv;
|
||
|
|
GLint j, index;
|
||
|
|
|
||
|
|
minv = *ivp; index=0;
|
||
|
|
|
||
|
|
//Reorder the vertices so that p0 is the one with the least y and x
|
||
|
|
for (i=0, cv=ivp; i<nout; i++, cv++)
|
||
|
|
{
|
||
|
|
if (__GL_VERTEX_COMPARE((*cv)->window.y, <, minv->window.y))
|
||
|
|
{
|
||
|
|
minv = *cv;
|
||
|
|
index = i;
|
||
|
|
}
|
||
|
|
else if (__GL_VERTEX_COMPARE((*cv)->window.y, ==, minv->window.y))
|
||
|
|
{
|
||
|
|
if (__GL_VERTEX_COMPARE((*cv)->window.x, <, minv->window.x))
|
||
|
|
{
|
||
|
|
minv = *cv;
|
||
|
|
index = i;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
DbgPrint ("MinIndex = %d\n", index);
|
||
|
|
|
||
|
|
j = index;
|
||
|
|
p0 = (__GLvertex *) ivp[j];
|
||
|
|
p1 = (__GLvertex *) ivp[(++j)%nout];
|
||
|
|
p2 = (__GLvertex *) ivp[(++j)%nout];
|
||
|
|
rt = gc->procs.renderTriangle;
|
||
|
|
if (nout == 3)
|
||
|
|
{
|
||
|
|
(*rt)(gc, p0, p1, p2);
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
for (i = 0; i < nout - 2; i++)
|
||
|
|
{
|
||
|
|
GLuint t1, t2;
|
||
|
|
if (i == 0)
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
** Third edge of first sub-triangle is always non-boundary
|
||
|
|
*/
|
||
|
|
// edgeflag is now part of has field.
|
||
|
|
t1 = p2->has & __GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
p2->has &= ~__GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
(*rt)(gc, p0, p1, p2);
|
||
|
|
p2->has |= t1;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
if (i == nout - 3)
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
** First edge of last sub-triangle is always
|
||
|
|
** non-boundary
|
||
|
|
*/
|
||
|
|
// edgeflag is now part of has field.
|
||
|
|
t1 = p0->has & __GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
p0->has &= ~__GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
(*rt)(gc, p0, p1, p2);
|
||
|
|
p0->has |= t1;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
** Interior sub-triangles have the first and last edge
|
||
|
|
** marked non-boundary
|
||
|
|
*/
|
||
|
|
// edgeflag is now part of has field.
|
||
|
|
t1 = p0->has & __GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
t2 = p2->has & __GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
p0->has &= ~__GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
p2->has &= ~__GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
(*rt)(gc, p0, p1, p2);
|
||
|
|
p0->has |= t1;
|
||
|
|
p2->has |= t2;
|
||
|
|
}
|
||
|
|
p1 = p2;
|
||
|
|
p2 = (__GLvertex *) ivp[(++j)%nout];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
#endif //GL_WIN_phong_shading
|
||
|
|
|
||
|
|
/*
|
||
|
|
** Subdivide the clipped polygon into triangles. Only convex polys
|
||
|
|
** are supported so this is okay to do. Non-convex polys will do
|
||
|
|
** something odd here, but thats the clients fault.
|
||
|
|
*/
|
||
|
|
p0 = *ivp++;
|
||
|
|
p1 = *ivp++;
|
||
|
|
p2 = *ivp++;
|
||
|
|
rt = gc->procs.renderTriangle;
|
||
|
|
if (nout == 3)
|
||
|
|
{
|
||
|
|
(*rt)(gc, p0, p1, p2);
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
for (i = 0; i < nout - 2; i++)
|
||
|
|
{
|
||
|
|
GLuint t1, t2;
|
||
|
|
if (i == 0)
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
** Third edge of first sub-triangle is always non-boundary
|
||
|
|
*/
|
||
|
|
// edgeflag is now part of has field.
|
||
|
|
t1 = p2->has & __GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
p2->has &= ~__GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
(*rt)(gc, p0, p1, p2);
|
||
|
|
p2->has |= t1;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
if (i == nout - 3)
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
** First edge of last sub-triangle is always
|
||
|
|
** non-boundary
|
||
|
|
*/
|
||
|
|
// edgeflag is now part of has field.
|
||
|
|
t1 = p0->has & __GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
p0->has &= ~__GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
(*rt)(gc, p0, p1, p2);
|
||
|
|
p0->has |= t1;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
** Interior sub-triangles have the first and last edge
|
||
|
|
** marked non-boundary
|
||
|
|
*/
|
||
|
|
// edgeflag is now part of has field.
|
||
|
|
t1 = p0->has & __GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
t2 = p2->has & __GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
p0->has &= ~__GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
p2->has &= ~__GL_HAS_EDGEFLAG_BOUNDARY;
|
||
|
|
(*rt)(gc, p0, p1, p2);
|
||
|
|
p0->has |= t1;
|
||
|
|
p2->has |= t2;
|
||
|
|
}
|
||
|
|
p1 = p2;
|
||
|
|
p2 = (__GLvertex *) *ivp++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
#if 0 //def GL_WIN_phong_shading
|
||
|
|
}
|
||
|
|
#endif //GL_WIN_phong_shading
|
||
|
|
}
|
||
|
|
|
||
|
|
void FASTCALL __glClipPolygon(__GLcontext *gc, __GLvertex *v0, GLint nv)
|
||
|
|
{
|
||
|
|
#ifdef NT
|
||
|
|
__GLvertex *iv[__GL_MAX_POLYGON_CLIP_SIZE];
|
||
|
|
#else
|
||
|
|
__GLvertex *iv[__GL_NVBUF];
|
||
|
|
#endif
|
||
|
|
__GLvertex **ivp;
|
||
|
|
GLint i;
|
||
|
|
GLuint andCodes, orCodes;
|
||
|
|
|
||
|
|
gc->vertex.provoking = v0;
|
||
|
|
|
||
|
|
/*
|
||
|
|
** Generate array of addresses of the verticies. And all the
|
||
|
|
** clip codes together while we are at it.
|
||
|
|
*/
|
||
|
|
ivp = &iv[0];
|
||
|
|
andCodes = (GLuint)(-1);
|
||
|
|
orCodes = 0;
|
||
|
|
for (i = nv; --i >= 0; ) {
|
||
|
|
andCodes &= v0->clipCode;
|
||
|
|
orCodes |= v0->clipCode;
|
||
|
|
*ivp++ = v0++;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (andCodes != 0) {
|
||
|
|
/*
|
||
|
|
** Trivially reject the polygon. If andCodes is non-zero then
|
||
|
|
** every vertex in the polygon is outside of the same set of
|
||
|
|
** clipping planes (at least one).
|
||
|
|
*/
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
__glDoPolygonClip(gc, &iv[0], nv, orCodes);
|
||
|
|
}
|
||
|
|
|
||
|
|
void FASTCALL __glClipTriangle(__GLcontext *gc, __GLvertex *a, __GLvertex *b,
|
||
|
|
__GLvertex *c, GLuint orCodes)
|
||
|
|
{
|
||
|
|
__GLvertex *iv[3];
|
||
|
|
|
||
|
|
iv[0] = a;
|
||
|
|
iv[1] = b;
|
||
|
|
iv[2] = c;
|
||
|
|
|
||
|
|
__glDoPolygonClip(gc, &iv[0], 3, orCodes);
|
||
|
|
}
|