static unsigned int compute_subdivisions(const BezierPath::Point& p0,
const BezierPath::Point& p1,
const BezierPath::Point& p2,
const BezierPath::Point& p3,
BezierPath::Coord flat)
{
vector2d<BezierPath::Coord> d01(p1.x() - p0.x(), p1.y() - p0.y());
vector2d<BezierPath::Coord> d12(p2.x() - p1.x(), p2.y() - p1.y());
vector2d<BezierPath::Coord> d23(p3.x() - p2.x(), p3.y() - p2.y());
vector2d<BezierPath::Coord> d03(p3.x() - p0.x(), p3.y() - p0.y());
vector2d<BezierPath::Coord> d01_12 = d12 - d01;
vector2d<BezierPath::Coord> d12_23 = d23 - d12;
double dist = norm(d03);
double dist2;
if (dist != 0) {
dist2 = __myabs(cross(d01_12, d03) / dist);
double tmp = __myabs(cross(d12_23, d03) / dist);
if (tmp > dist2) {
dist2 = tmp;
}
} else {
vector2d<BezierPath::Coord> d0(p0.x(), p0.y());
dist2 = norm(vector2d<BezierPath::Coord>(d01_12 - d0));
double tmp = norm(vector2d<BezierPath::Coord>(d12_23 - d0));
if (tmp > dist2) {
dist2 = tmp;
}
}
unsigned int subdivisions = 0;
if (dist2 > 0) {
subdivisions = log4(long((3.0 / 4.0) * dist2 / flat + 0.5));
}
return subdivisions;
}
void render() {
glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
zviewpointSetupView();
const int MAX_TRIS = 1000000;
static Triangle tris[MAX_TRIS];
int triCount = 0;
const int steps = 60;
const float stepsf = (float)steps;
Rod r0( FVec3(-0.3f,0.f,0.f), FVec3(+0.f,0.f,0.f), Cloud_r );
Rod r1( FVec3(0.f,0.f,0.f), FVec3(0.2f,0.5f,0.f), Cloud_r );
Sphere s0( FVec3(-.5f, -.5f, 0.f), 0.25f );
Surface *surfaces[] = {
(Surface *)&r0,
(Surface *)&r1,
(Surface *)&s0
};
int surfacesCount = sizeof(surfaces) / sizeof(surfaces[0]);
float f[steps][steps][steps];
for( int xi=0; xi<steps; xi++ ) {
for( int yi=0; yi<steps; yi++ ) {
for( int zi=0; zi<steps; zi++ ) {
FVec3 p( 2.f*(float)xi/stepsf-1.f, 2.f*(float)yi/stepsf-1.f, 2.f*(float)zi/stepsf-1.f );
f[xi][yi][zi] = 0.f;
for( int i=0; i<surfacesCount; i++ ) {
f[xi][yi][zi] += surfaces[i]->surface( p );
}
}
}
}
for( int xi=0; xi<steps-1; xi++ ) {
for( int yi=0; yi<steps-1; yi++ ) {
for( int zi=0; zi<steps-1; zi++ ) {
GridCell g;
float x0 = 2.f*(float)(xi+0)/stepsf-1.f;
float x1 = 2.f*(float)(xi+1)/stepsf-1.f;
float y0 = 2.f*(float)(yi+0)/stepsf-1.f;
float y1 = 2.f*(float)(yi+1)/stepsf-1.f;
float z0 = 2.f*(float)(zi+0)/stepsf-1.f;
float z1 = 2.f*(float)(zi+1)/stepsf-1.f;
g.p[0] = FVec3( x0, y0, z0 );
g.p[1] = FVec3( x1, y0, z0 );
g.p[2] = FVec3( x1, y1, z0 );
g.p[3] = FVec3( x0, y1, z0 );
g.p[4] = FVec3( x0, y0, z1 );
g.p[5] = FVec3( x1, y0, z1 );
g.p[6] = FVec3( x1, y1, z1 );
g.p[7] = FVec3( x0, y1, z1 );
g.val[0] = f[xi+0][yi+0][zi+0];
g.val[1] = f[xi+1][yi+0][zi+0];
g.val[2] = f[xi+1][yi+1][zi+0];
g.val[3] = f[xi+0][yi+1][zi+0];
g.val[4] = f[xi+0][yi+0][zi+1];
g.val[5] = f[xi+1][yi+0][zi+1];
g.val[6] = f[xi+1][yi+1][zi+1];
g.val[7] = f[xi+0][yi+1][zi+1];
triCount += polygonise( g, Cloud_r, &tris[triCount] );
assert( triCount < MAX_TRIS );
}
}
}
DiscWarp dw( FVec3(-0.2f,0.f,0.f), FVec3(1.f,0.f,0.f) );
for( int i=0; i<triCount; i++ ) {
tris[i].p[0] = dw.warp( tris[i].p[0] );
tris[i].p[1] = dw.warp( tris[i].p[1] );
tris[i].p[2] = dw.warp( tris[i].p[2] );
}
dw.draw();
static unsigned int triList[MAX_TRIS*3];
static FVec3 normals[MAX_TRIS*3];
ZGLLight light0;
light0.resetToDefaults();
light0.active = 1;
light0.ambient[0] = 0.05f;
light0.ambient[1] = 0.05f;
light0.ambient[2] = 0.05f;
light0.diffuse[0] = 0.8f;
light0.diffuse[1] = 0.2f;
light0.diffuse[2] = 0.2f;
light0.dir[0] = 10.f;
light0.dir[1] = 0.f;
light0.dir[2] = 0.f;
light0.makeDirectional();
light0.setLightNumber( 0 );
ZGLLight light1;
light1.resetToDefaults();
light1.active = 1;
light1.ambient[0] = 0.05f;
light1.ambient[1] = 0.05f;
light1.ambient[2] = 0.05f;
light1.diffuse[0] = 0.2f;
light1.diffuse[1] = 0.2f;
light1.diffuse[2] = 0.8f;
light1.dir[0] = -10.f;
light1.dir[1] = -10.f;
light1.dir[2] = 0.f;
light1.makeDirectional();
light1.setLightNumber( 1 );
glEnable( GL_COLOR_MATERIAL );
glEnable( GL_LIGHTING );
glEnable( GL_LIGHT0 );
glEnable( GL_LIGHT1 );
glEnable( GL_DEPTH_TEST );
glEnable( GL_NORMALIZE );
light0.setGL();
light1.setGL();
for( int i=0; i<triCount; i++ ) {
FVec3 d10( tris[i].p[1] );
d10.sub( tris[i].p[0] );
FVec3 d20( tris[i].p[2] );
d20.sub( tris[i].p[0] );
normals[i*3+0] = d20;
normals[i*3+0].cross( d10 );
FVec3 d01( tris[i].p[0] );
d01.sub( tris[i].p[1] );
FVec3 d21( tris[i].p[2] );
d21.sub( tris[i].p[1] );
normals[i*3+1] = d01;
normals[i*3+1].cross( d21 );
FVec3 d02( tris[i].p[0] );
d02.sub( tris[i].p[2] );
FVec3 d12( tris[i].p[1] );
d12.sub( tris[i].p[2] );
normals[i*3+2] = d12;
normals[i*3+2].cross( d02 );
triList[i*3+0] = i*3+0;
triList[i*3+1] = i*3+1;
triList[i*3+2] = i*3+2;
}
glColor3ub( 255, 255, 255 );
glEnableClientState( GL_VERTEX_ARRAY );
glVertexPointer( 3, GL_FLOAT, 0, &tris[0] );
glEnableClientState( GL_NORMAL_ARRAY );
glNormalPointer( GL_FLOAT, 0, &normals[0] );
glDrawElements( GL_TRIANGLES, triCount*3, GL_UNSIGNED_INT, &triList[0] );
}
