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Diffstat (limited to 'src/classes/com/sun/opengl/impl/tessellator/Geom.java')
-rw-r--r-- | src/classes/com/sun/opengl/impl/tessellator/Geom.java | 318 |
1 files changed, 0 insertions, 318 deletions
diff --git a/src/classes/com/sun/opengl/impl/tessellator/Geom.java b/src/classes/com/sun/opengl/impl/tessellator/Geom.java deleted file mode 100644 index 11e17d535..000000000 --- a/src/classes/com/sun/opengl/impl/tessellator/Geom.java +++ /dev/null @@ -1,318 +0,0 @@ -/* -* Portions Copyright (C) 2003-2006 Sun Microsystems, Inc. -* All rights reserved. -*/ - -/* -** License Applicability. Except to the extent portions of this file are -** made subject to an alternative license as permitted in the SGI Free -** Software License B, Version 1.1 (the "License"), the contents of this -** file are subject only to the provisions of the License. You may not use -** this file except in compliance with the License. You may obtain a copy -** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600 -** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at: -** -** http://oss.sgi.com/projects/FreeB -** -** Note that, as provided in the License, the Software is distributed on an -** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS -** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND -** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A -** PARTICULAR PURPOSE, AND NON-INFRINGEMENT. -** -** NOTE: The Original Code (as defined below) has been licensed to Sun -** Microsystems, Inc. ("Sun") under the SGI Free Software License B -** (Version 1.1), shown above ("SGI License"). Pursuant to Section -** 3.2(3) of the SGI License, Sun is distributing the Covered Code to -** you under an alternative license ("Alternative License"). This -** Alternative License includes all of the provisions of the SGI License -** except that Section 2.2 and 11 are omitted. Any differences between -** the Alternative License and the SGI License are offered solely by Sun -** and not by SGI. -** -** Original Code. The Original Code is: OpenGL Sample Implementation, -** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics, -** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc. -** Copyright in any portions created by third parties is as indicated -** elsewhere herein. All Rights Reserved. -** -** Additional Notice Provisions: The application programming interfaces -** established by SGI in conjunction with the Original Code are The -** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released -** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version -** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X -** Window System(R) (Version 1.3), released October 19, 1998. This software -** was created using the OpenGL(R) version 1.2.1 Sample Implementation -** published by SGI, but has not been independently verified as being -** compliant with the OpenGL(R) version 1.2.1 Specification. -** -** Author: Eric Veach, July 1994 -** Java Port: Pepijn Van Eeckhoudt, July 2003 -** Java Port: Nathan Parker Burg, August 2003 -*/ -package com.sun.opengl.impl.tessellator; - -class Geom { - private Geom() { - } - - /* Given three vertices u,v,w such that VertLeq(u,v) && VertLeq(v,w), - * evaluates the t-coord of the edge uw at the s-coord of the vertex v. - * Returns v->t - (uw)(v->s), ie. the signed distance from uw to v. - * If uw is vertical (and thus passes thru v), the result is zero. - * - * The calculation is extremely accurate and stable, even when v - * is very close to u or w. In particular if we set v->t = 0 and - * let r be the negated result (this evaluates (uw)(v->s)), then - * r is guaranteed to satisfy MIN(u->t,w->t) <= r <= MAX(u->t,w->t). - */ - static double EdgeEval(GLUvertex u, GLUvertex v, GLUvertex w) { - double gapL, gapR; - - assert (VertLeq(u, v) && VertLeq(v, w)); - - gapL = v.s - u.s; - gapR = w.s - v.s; - - if (gapL + gapR > 0) { - if (gapL < gapR) { - return (v.t - u.t) + (u.t - w.t) * (gapL / (gapL + gapR)); - } else { - return (v.t - w.t) + (w.t - u.t) * (gapR / (gapL + gapR)); - } - } - /* vertical line */ - return 0; - } - - static double EdgeSign(GLUvertex u, GLUvertex v, GLUvertex w) { - double gapL, gapR; - - assert (VertLeq(u, v) && VertLeq(v, w)); - - gapL = v.s - u.s; - gapR = w.s - v.s; - - if (gapL + gapR > 0) { - return (v.t - w.t) * gapL + (v.t - u.t) * gapR; - } - /* vertical line */ - return 0; - } - - - /*********************************************************************** - * Define versions of EdgeSign, EdgeEval with s and t transposed. - */ - - static double TransEval(GLUvertex u, GLUvertex v, GLUvertex w) { - /* Given three vertices u,v,w such that TransLeq(u,v) && TransLeq(v,w), - * evaluates the t-coord of the edge uw at the s-coord of the vertex v. - * Returns v->s - (uw)(v->t), ie. the signed distance from uw to v. - * If uw is vertical (and thus passes thru v), the result is zero. - * - * The calculation is extremely accurate and stable, even when v - * is very close to u or w. In particular if we set v->s = 0 and - * let r be the negated result (this evaluates (uw)(v->t)), then - * r is guaranteed to satisfy MIN(u->s,w->s) <= r <= MAX(u->s,w->s). - */ - double gapL, gapR; - - assert (TransLeq(u, v) && TransLeq(v, w)); - - gapL = v.t - u.t; - gapR = w.t - v.t; - - if (gapL + gapR > 0) { - if (gapL < gapR) { - return (v.s - u.s) + (u.s - w.s) * (gapL / (gapL + gapR)); - } else { - return (v.s - w.s) + (w.s - u.s) * (gapR / (gapL + gapR)); - } - } - /* vertical line */ - return 0; - } - - static double TransSign(GLUvertex u, GLUvertex v, GLUvertex w) { - /* Returns a number whose sign matches TransEval(u,v,w) but which - * is cheaper to evaluate. Returns > 0, == 0 , or < 0 - * as v is above, on, or below the edge uw. - */ - double gapL, gapR; - - assert (TransLeq(u, v) && TransLeq(v, w)); - - gapL = v.t - u.t; - gapR = w.t - v.t; - - if (gapL + gapR > 0) { - return (v.s - w.s) * gapL + (v.s - u.s) * gapR; - } - /* vertical line */ - return 0; - } - - - static boolean VertCCW(GLUvertex u, GLUvertex v, GLUvertex w) { - /* For almost-degenerate situations, the results are not reliable. - * Unless the floating-point arithmetic can be performed without - * rounding errors, *any* implementation will give incorrect results - * on some degenerate inputs, so the client must have some way to - * handle this situation. - */ - return (u.s * (v.t - w.t) + v.s * (w.t - u.t) + w.s * (u.t - v.t)) >= 0; - } - -/* Given parameters a,x,b,y returns the value (b*x+a*y)/(a+b), - * or (x+y)/2 if a==b==0. It requires that a,b >= 0, and enforces - * this in the rare case that one argument is slightly negative. - * The implementation is extremely stable numerically. - * In particular it guarantees that the result r satisfies - * MIN(x,y) <= r <= MAX(x,y), and the results are very accurate - * even when a and b differ greatly in magnitude. - */ - static double Interpolate(double a, double x, double b, double y) { - a = (a < 0) ? 0 : a; - b = (b < 0) ? 0 : b; - if (a <= b) { - if (b == 0) { - return (x + y) / 2.0; - } else { - return (x + (y - x) * (a / (a + b))); - } - } else { - return (y + (x - y) * (b / (a + b))); - } - } - - static void EdgeIntersect(GLUvertex o1, GLUvertex d1, - GLUvertex o2, GLUvertex d2, - GLUvertex v) -/* Given edges (o1,d1) and (o2,d2), compute their point of intersection. - * The computed point is guaranteed to lie in the intersection of the - * bounding rectangles defined by each edge. - */ { - double z1, z2; - - /* This is certainly not the most efficient way to find the intersection - * of two line segments, but it is very numerically stable. - * - * Strategy: find the two middle vertices in the VertLeq ordering, - * and interpolate the intersection s-value from these. Then repeat - * using the TransLeq ordering to find the intersection t-value. - */ - - if (!VertLeq(o1, d1)) { - GLUvertex temp = o1; - o1 = d1; - d1 = temp; - } - if (!VertLeq(o2, d2)) { - GLUvertex temp = o2; - o2 = d2; - d2 = temp; - } - if (!VertLeq(o1, o2)) { - GLUvertex temp = o1; - o1 = o2; - o2 = temp; - temp = d1; - d1 = d2; - d2 = temp; - } - - if (!VertLeq(o2, d1)) { - /* Technically, no intersection -- do our best */ - v.s = (o2.s + d1.s) / 2.0; - } else if (VertLeq(d1, d2)) { - /* Interpolate between o2 and d1 */ - z1 = EdgeEval(o1, o2, d1); - z2 = EdgeEval(o2, d1, d2); - if (z1 + z2 < 0) { - z1 = -z1; - z2 = -z2; - } - v.s = Interpolate(z1, o2.s, z2, d1.s); - } else { - /* Interpolate between o2 and d2 */ - z1 = EdgeSign(o1, o2, d1); - z2 = -EdgeSign(o1, d2, d1); - if (z1 + z2 < 0) { - z1 = -z1; - z2 = -z2; - } - v.s = Interpolate(z1, o2.s, z2, d2.s); - } - - /* Now repeat the process for t */ - - if (!TransLeq(o1, d1)) { - GLUvertex temp = o1; - o1 = d1; - d1 = temp; - } - if (!TransLeq(o2, d2)) { - GLUvertex temp = o2; - o2 = d2; - d2 = temp; - } - if (!TransLeq(o1, o2)) { - GLUvertex temp = o2; - o2 = o1; - o1 = temp; - temp = d2; - d2 = d1; - d1 = temp; - } - - if (!TransLeq(o2, d1)) { - /* Technically, no intersection -- do our best */ - v.t = (o2.t + d1.t) / 2.0; - } else if (TransLeq(d1, d2)) { - /* Interpolate between o2 and d1 */ - z1 = TransEval(o1, o2, d1); - z2 = TransEval(o2, d1, d2); - if (z1 + z2 < 0) { - z1 = -z1; - z2 = -z2; - } - v.t = Interpolate(z1, o2.t, z2, d1.t); - } else { - /* Interpolate between o2 and d2 */ - z1 = TransSign(o1, o2, d1); - z2 = -TransSign(o1, d2, d1); - if (z1 + z2 < 0) { - z1 = -z1; - z2 = -z2; - } - v.t = Interpolate(z1, o2.t, z2, d2.t); - } - } - - static boolean VertEq(GLUvertex u, GLUvertex v) { - return u.s == v.s && u.t == v.t; - } - - static boolean VertLeq(GLUvertex u, GLUvertex v) { - return u.s < v.s || (u.s == v.s && u.t <= v.t); - } - -/* Versions of VertLeq, EdgeSign, EdgeEval with s and t transposed. */ - - static boolean TransLeq(GLUvertex u, GLUvertex v) { - return u.t < v.t || (u.t == v.t && u.s <= v.s); - } - - static boolean EdgeGoesLeft(GLUhalfEdge e) { - return VertLeq(e.Sym.Org, e.Org); - } - - static boolean EdgeGoesRight(GLUhalfEdge e) { - return VertLeq(e.Org, e.Sym.Org); - } - - static double VertL1dist(GLUvertex u, GLUvertex v) { - return Math.abs(u.s - v.s) + Math.abs(u.t - v.t); - } -} |