Skip to content
Snippets Groups Projects
Commit 00418abb authored by Christophe Geuzaine's avatar Christophe Geuzaine
Browse files 

better solution for offset
parent a9b14a1d
Branches
Tags
No related merge requests found
Show whitespace changes
Inline Side-by-side
Showing
with 71 additions and 73 deletions
Graphics/gl2ps.cpp
+ 71
− 73
View file @ 00418abb
/* $Id: gl2ps.cpp,v 1.90 2004-11-22 08:10:29 geuzaine Exp $ */
/* $Id: gl2ps.cpp,v 1.91 2004-11-22 18:00:30 geuzaine Exp $ */
/*
* GL2PS, an OpenGL to PostScript Printing Library
* Copyright (C) 1999-2004 Christophe Geuzaine <geuz@geuz.org>
......@@ -62,8 +62,13 @@
*
*********************************************************************/
/* Magic numbers */
/* Magic numbers (assuming that the order of magnitude of window
coordinates is 10^3) */
#define GL2PS_EPSILON 5.0e-3F
#define GL2PS_ZSCALE 1000.0F
#define GL2PS_ZOFFSET 1.0F
#define GL2PS_ZOFFSET_LARGE 20.0F
#define GL2PS_ZERO(arg) (fabs(arg) < 1.e-20)
/* Primitive types */
......@@ -188,7 +193,7 @@ typedef struct {
GLint format, sort, options, colorsize, colormode, buffersize;
char *title, *producer, *filename;
GLboolean boundary, blending;
GLfloat epsilon, *feedback, offset[2], lastlinewidth;
GLfloat *feedback, offset[2], lastlinewidth;
GLint viewport[4], blendfunc[2];
GL2PSrgba *colormap, lastrgba, threshold;
GL2PSlist *primitives;
......@@ -926,15 +931,15 @@ static GLint gl2psTestSplitPrimitive(GL2PSprimitive *prim, GL2PSplane plane)
else{
for(i = 0; i < prim->numverts; i++){
j = gl2psGetIndex(i, prim->numverts);
if(d[j] > gl2ps->epsilon){
if(d[j] > GL2PS_EPSILON){
if(type == GL2PS_COINCIDENT) type = GL2PS_IN_BACK_OF;
else if(type != GL2PS_IN_BACK_OF) return 1;
if(d[i] < -gl2ps->epsilon) return 1;
if(d[i] < -GL2PS_EPSILON) return 1;
}
else if(d[j] < -gl2ps->epsilon){
else if(d[j] < -GL2PS_EPSILON){
if(type == GL2PS_COINCIDENT) type = GL2PS_IN_FRONT_OF;
else if(type != GL2PS_IN_FRONT_OF) return 1;
if(d[i] > gl2ps->epsilon) return 1;
if(d[i] > GL2PS_EPSILON) return 1;
}
}
}
......@@ -956,27 +961,27 @@ static GLint gl2psSplitPrimitive(GL2PSprimitive *prim, GL2PSplane plane,
switch(prim->type){
case GL2PS_POINT :
if(d[0] > gl2ps->epsilon) type = GL2PS_IN_BACK_OF;
else if(d[0] < -gl2ps->epsilon) type = GL2PS_IN_FRONT_OF;
if(d[0] > GL2PS_EPSILON) type = GL2PS_IN_BACK_OF;
else if(d[0] < -GL2PS_EPSILON) type = GL2PS_IN_FRONT_OF;
else type = GL2PS_COINCIDENT;
break;
default :
for(i = 0; i < prim->numverts; i++){
j = gl2psGetIndex(i, prim->numverts);
if(d[j] > gl2ps->epsilon){
if(d[j] > GL2PS_EPSILON){
if(type == GL2PS_COINCIDENT) type = GL2PS_IN_BACK_OF;
else if(type != GL2PS_IN_BACK_OF) type = GL2PS_SPANNING;
if(d[i] < -gl2ps->epsilon){
if(d[i] < -GL2PS_EPSILON){
gl2psAddIndex(in0, in1, &in, i, j);
gl2psAddIndex(out0, out1, &out, i, j);
type = GL2PS_SPANNING;
}
gl2psAddIndex(out0, out1, &out, j, -1);
}
else if(d[j] < -gl2ps->epsilon){
else if(d[j] < -GL2PS_EPSILON){
if(type == GL2PS_COINCIDENT) type = GL2PS_IN_FRONT_OF;
else if(type != GL2PS_IN_FRONT_OF) type = GL2PS_SPANNING;
if(d[i] > gl2ps->epsilon){
if(d[i] > GL2PS_EPSILON){
gl2psAddIndex(in0, in1, &in, i, j);
gl2psAddIndex(out0, out1, &out, i, j);
type = GL2PS_SPANNING;
......@@ -1276,12 +1281,12 @@ static void gl2psTraverseBspTree(GL2PSbsptree *tree, GL2PSxyz eye, GLfloat epsil
}
}
static void gl2psSetPrecisionAndApplyOffsets()
static void gl2psRescaleAndOffset()
{
GL2PSprimitive *prim;
GLfloat minZ, maxZ, simple;
GLfloat minZ, maxZ, rangeZ, scaleZ;
GLfloat factor, units, area, dZ, dZdX, dZdY, maxdZ;
int i, j, offset = 0;
int i, j;
if(!gl2psListNbr(gl2ps->primitives))
return;
......@@ -1289,7 +1294,6 @@ static void gl2psSetPrecisionAndApplyOffsets()
/* get z-buffer range */
prim = *(GL2PSprimitive**)gl2psListPointer(gl2ps->primitives, 0);
minZ = maxZ = prim->verts[0].xyz[2];
if(prim->offset) offset = 1;
for(i = 1; i < prim->numverts; i++){
if(prim->verts[i].xyz[2] < minZ) minZ = prim->verts[i].xyz[2];
if(prim->verts[i].xyz[2] > maxZ) maxZ = prim->verts[i].xyz[2];
......@@ -1300,37 +1304,33 @@ static void gl2psSetPrecisionAndApplyOffsets()
if(prim->verts[j].xyz[2] < minZ) minZ = prim->verts[j].xyz[2];
if(prim->verts[j].xyz[2] > maxZ) maxZ = prim->verts[j].xyz[2];
}
if(prim->offset) offset = 1;
}
rangeZ = (maxZ - minZ);
/* set precision */
gl2ps->epsilon = (maxZ - minZ) / 5000.0F;
simple = (maxZ - minZ) / 1000.0F;
if(GL2PS_ZERO(gl2ps->epsilon)) gl2ps->epsilon = 0.0002F;
if(GL2PS_ZERO(simple)) simple = 0.001F;
/* rescale z-buffer coordinate in [0,GL2PS_ZSCALE], to make it of
the same order of magnitude as the x and y coordinates */
scaleZ = GL2PS_ZERO(rangeZ) ? GL2PS_ZSCALE : GL2PS_ZSCALE / rangeZ;
/* apply offsets */
if(gl2ps->options & GL2PS_SIMPLE_LINE_OFFSET){
for(i = 0; i < gl2psListNbr(gl2ps->primitives); i++){
prim = *(GL2PSprimitive**)gl2psListPointer(gl2ps->primitives, i);
if(prim->type == GL2PS_LINE){
for(j = 0; j < prim->numverts; j++){
prim->verts[j].xyz[2] *= scaleZ;
}
if((gl2ps->options & GL2PS_SIMPLE_LINE_OFFSET) &&
(prim->type == GL2PS_LINE)){
if(gl2ps->sort == GL2PS_SIMPLE_SORT){
prim->verts[0].xyz[2] -= simple * 20.0F;
prim->verts[1].xyz[2] -= simple * 20.0F;
prim->verts[0].xyz[2] -= GL2PS_ZOFFSET_LARGE;
prim->verts[1].xyz[2] -= GL2PS_ZOFFSET_LARGE;
}
else{
prim->verts[0].xyz[2] -= simple;
prim->verts[1].xyz[2] -= simple;
}
prim->verts[0].xyz[2] -= GL2PS_ZOFFSET;
prim->verts[1].xyz[2] -= GL2PS_ZOFFSET;
}
}
}
else if(offset){ /* at least one primitive needs to be offsetted */
else if(prim->offset && (prim->type == GL2PS_TRIANGLE)){
factor = gl2ps->offset[0];
units = gl2ps->offset[1];
for(i = 0; i < gl2psListNbr(gl2ps->primitives); i++){
prim = *(GL2PSprimitive**)gl2psListPointer(gl2ps->primitives, i);
if(prim->offset && prim->type == GL2PS_TRIANGLE){
area =
(prim->verts[1].xyz[0] - prim->verts[0].xyz[0]) *
(prim->verts[2].xyz[1] - prim->verts[1].xyz[1]) -
......@@ -1354,7 +1354,6 @@ static void gl2psSetPrecisionAndApplyOffsets()
}
}
}
}
/*********************************************************************
*
......@@ -1370,7 +1369,7 @@ static GLint gl2psGetPlaneFromPoints(GL2PSxyz a, GL2PSxyz b, GL2PSplane plane)
plane[1] = a[0] - b[0];
n = (GLfloat)sqrt(plane[0]*plane[0] + plane[1]*plane[1]);
plane[2] = 0.0F;
if(n != 0.0){
if(!GL2PS_ZERO(n)){
plane[0] /= n;
plane[1] /= n;
plane[3] = -plane[0]*a[0]-plane[1]*a[1];
......@@ -1399,8 +1398,8 @@ static GLint gl2psCheckPoint(GL2PSxyz point, GL2PSplane plane)
GLfloat pt_dis;
pt_dis = gl2psComparePointPlane(point, plane);
if(pt_dis > gl2ps->epsilon) return GL2PS_POINT_INFRONT;
else if(pt_dis < -gl2ps->epsilon) return GL2PS_POINT_BACK;
if(pt_dis > GL2PS_EPSILON) return GL2PS_POINT_INFRONT;
else if(pt_dis < -GL2PS_EPSILON) return GL2PS_POINT_BACK;
else return GL2PS_POINT_COINCIDENT;
}
......@@ -4310,7 +4309,7 @@ static GLint gl2psPrintPrimitives(void)
return GL2PS_NO_FEEDBACK;
}
gl2psSetPrecisionAndApplyOffsets();
gl2psRescaleAndOffset();
switch(gl2ps->format){
case GL2PS_TEX :
......@@ -4348,11 +4347,11 @@ static GLint gl2psPrintPrimitives(void)
gl2psBuildBspTree(root, gl2ps->primitives);
if(GL_TRUE == gl2ps->boundary) gl2psBuildPolygonBoundary(root);
if(gl2ps->options & GL2PS_OCCLUSION_CULL){
gl2psTraverseBspTree(root, eye, -gl2ps->epsilon, gl2psLess,
gl2psTraverseBspTree(root, eye, -GL2PS_EPSILON, gl2psLess,
gl2psAddInImageTree, 1);
gl2psFreeBspImageTree(&gl2ps->imagetree);
}
gl2psTraverseBspTree(root, eye, gl2ps->epsilon, gl2psGreater,
gl2psTraverseBspTree(root, eye, GL2PS_EPSILON, gl2psGreater,
pprim, 0);
gl2psFreeBspTree(&root);
/* reallocate the primitive list (it's been deleted by
......@@ -4397,7 +4396,6 @@ GL2PSDLL_API GLint gl2psBeginPage(const char *title, const char *producer,
gl2ps->compress = NULL;
gl2ps->imagemap_head = NULL;
gl2ps->imagemap_tail = NULL;
gl2ps->epsilon = 0.0F; /* adjusted later according to z-buffer values */
if(gl2ps->options & GL2PS_USE_CURRENT_VIEWPORT){
glGetIntegerv(GL_VIEWPORT, gl2ps->viewport);
......
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Please register or to comment