static GLOBJECT * createGroundPlane()
{
const int scale = 4;
const int yBegin = -15, yEnd = 15; // ends are non-inclusive
const int xBegin = -15, xEnd = 15;
const long triangleCount = (yEnd - yBegin) * (xEnd - xBegin) * 2;
const long vertices = triangleCount * 3;
GLOBJECT *result;
int x, y;
long currentVertex, currentQuad;
result = newGLObject(vertices, 2, 0);
if (result == NULL)
return NULL;
currentQuad = 0;
currentVertex = 0;
for (y = yBegin; y < yEnd; ++y)
{
for (x = xBegin; x < xEnd; ++x)
{
GLubyte color;
int i, a;
color = (GLubyte)((randomUInt() & 0x5f) + 81); // 101 1111
for (i = currentVertex * 4; i < (currentVertex + 6) * 4; i += 4)
{
result->colorArray[i] = color;
result->colorArray[i + 1] = color;
result->colorArray[i + 2] = color;
result->colorArray[i + 3] = 0;
}
// Axis bits for quad triangles:
// x: 011100 (0x1c), y: 110001 (0x31) (clockwise)
// x: 001110 (0x0e), y: 100011 (0x23) (counter-clockwise)
for (a = 0; a < 6; ++a)
{
const int xm = x + ((0x1c >> a) & 1);
const int ym = y + ((0x31 >> a) & 1);
const float m = (float)(cos(xm * 2) * sin(ym * 4) * 0.75f);
result->vertexArray[currentVertex * 2] =
FIXED(xm * scale + m);
result->vertexArray[currentVertex * 2 + 1] =
FIXED(ym * scale + m);
++currentVertex;
}
++currentQuad;
}
}
return result;
}
// Creates and returns a supershape object.
// Based on Paul Bourke's POV-Ray implementation.
// http://astronomy.swin.edu.au/~pbourke/povray/supershape/
static GLOBJECT * createSuperShape(const float *params)
{
const int resol1 = (int)params[SUPERSHAPE_PARAMS - 3];
const int resol2 = (int)params[SUPERSHAPE_PARAMS - 2];
// latitude 0 to pi/2 for no mirrored bottom
// (latitudeBegin==0 for -pi/2 to pi/2 originally)
const int latitudeBegin = resol2 / 4;
const int latitudeEnd = resol2 / 2; // non-inclusive
const int longitudeCount = resol1;
const int latitudeCount = latitudeEnd - latitudeBegin;
const long triangleCount = longitudeCount * latitudeCount * 2;
const long vertices = triangleCount * 3;
GLOBJECT *result;
float baseColor[3];
int a, longitude, latitude;
long currentVertex, currentQuad;
result = newGLObject(vertices, 3, 1);
if (result == NULL)
return NULL;
for (a = 0; a < 3; ++a)
baseColor[a] = ((randomUInt() % 155) + 100) / 255.f;
currentQuad = 0;
currentVertex = 0;
// longitude -pi to pi
for (longitude = 0; longitude < longitudeCount; ++longitude)
{
// latitude 0 to pi/2
for (latitude = latitudeBegin; latitude < latitudeEnd; ++latitude)
{
float t1 = -PI + longitude * 2 * PI / resol1;
float t2 = -PI + (longitude + 1) * 2 * PI / resol1;
float p1 = -PI / 2 + latitude * 2 * PI / resol2;
float p2 = -PI / 2 + (latitude + 1) * 2 * PI / resol2;
float r0, r1, r2, r3;
r0 = ssFunc(t1, params);
r1 = ssFunc(p1, ¶ms[6]);
r2 = ssFunc(t2, params);
r3 = ssFunc(p2, ¶ms[6]);
if (r0 != 0 && r1 != 0 && r2 != 0 && r3 != 0)
{
VECTOR3 pa, pb, pc, pd;
VECTOR3 v1, v2, n;
float ca;
int i;
//float lenSq, invLenSq;
superShapeMap(&pa, r0, r1, t1, p1);
superShapeMap(&pb, r2, r1, t2, p1);
superShapeMap(&pc, r2, r3, t2, p2);
superShapeMap(&pd, r0, r3, t1, p2);
// kludge to set lower edge of the object to fixed level
if (latitude == latitudeBegin + 1)
pa.z = pb.z = 0;
vector3Sub(&v1, &pb, &pa);
vector3Sub(&v2, &pd, &pa);
// Calculate normal with cross product.
/* i j k i j
* v1.x v1.y v1.z | v1.x v1.y
* v2.x v2.y v2.z | v2.x v2.y
*/
n.x = v1.y * v2.z - v1.z * v2.y;
n.y = v1.z * v2.x - v1.x * v2.z;
n.z = v1.x * v2.y - v1.y * v2.x;
/* Pre-normalization of the normals is disabled here because
* they will be normalized anyway later due to automatic
* normalization (GL_NORMALIZE). It is enabled because the
* objects are scaled with glScale.
*/
/*
lenSq = n.x * n.x + n.y * n.y + n.z * n.z;
invLenSq = (float)(1 / sqrt(lenSq));
n.x *= invLenSq;
n.y *= invLenSq;
n.z *= invLenSq;
*/
ca = pa.z + 0.5f;
for (i = currentVertex * 3;
i < (currentVertex + 6) * 3;
i += 3)
{
result->normalArray[i] = FIXED(n.x);
result->normalArray[i + 1] = FIXED(n.y);
result->normalArray[i + 2] = FIXED(n.z);
}
for (i = currentVertex * 4;
i < (currentVertex + 6) * 4;
i += 4)
{
int a, color[3];
for (a = 0; a < 3; ++a)
{
color[a] = (int)(ca * baseColor[a] * 255);
if (color[a] > 255) color[a] = 255;
}
result->colorArray[i] = (GLubyte)color[0];
result->colorArray[i + 1] = (GLubyte)color[1];
result->colorArray[i + 2] = (GLubyte)color[2];
result->colorArray[i + 3] = 0;
}
result->vertexArray[currentVertex * 3] = FIXED(pa.x);
result->vertexArray[currentVertex * 3 + 1] = FIXED(pa.y);
result->vertexArray[currentVertex * 3 + 2] = FIXED(pa.z);
++currentVertex;
result->vertexArray[currentVertex * 3] = FIXED(pb.x);
result->vertexArray[currentVertex * 3 + 1] = FIXED(pb.y);
result->vertexArray[currentVertex * 3 + 2] = FIXED(pb.z);
++currentVertex;
result->vertexArray[currentVertex * 3] = FIXED(pd.x);
result->vertexArray[currentVertex * 3 + 1] = FIXED(pd.y);
result->vertexArray[currentVertex * 3 + 2] = FIXED(pd.z);
++currentVertex;
result->vertexArray[currentVertex * 3] = FIXED(pb.x);
result->vertexArray[currentVertex * 3 + 1] = FIXED(pb.y);
result->vertexArray[currentVertex * 3 + 2] = FIXED(pb.z);
++currentVertex;
result->vertexArray[currentVertex * 3] = FIXED(pc.x);
result->vertexArray[currentVertex * 3 + 1] = FIXED(pc.y);
result->vertexArray[currentVertex * 3 + 2] = FIXED(pc.z);
++currentVertex;
result->vertexArray[currentVertex * 3] = FIXED(pd.x);
result->vertexArray[currentVertex * 3 + 1] = FIXED(pd.y);
result->vertexArray[currentVertex * 3 + 2] = FIXED(pd.z);
++currentVertex;
} // r0 && r1 && r2 && r3
++currentQuad;
} // latitude
} // longitude
// Set number of vertices in object to the actual amount created.
result->count = currentVertex;
return result;
}
static GLOBJECT * createSuperShape(const float *params)
{
const int resol1 = (int)params[SUPERSHAPE_PARAMS - 3];
const int resol2 = (int)params[SUPERSHAPE_PARAMS - 2];
const int latitudeBegin = resol2 / 4;
const int latitudeEnd = resol2 / 2;
const int longitudeCount = resol1;
const int latitudeCount = latitudeEnd - latitudeBegin;
const long triangleCount = longitudeCount * latitudeCount * 2;
const long vertices = triangleCount * 3;
GLOBJECT *result;
float baseColor[3];
int a, longitude, latitude;
long currentVertex, currentQuad;
result = newGLObject(vertices, 3, 1);
if (result == NULL)
return NULL;
for (a = 0; a < 3; ++a)
baseColor[a] = ((randomUInt() % 155) + 100) / 255.f;
currentQuad = 0;
currentVertex = 0;
for (longitude = 0; longitude < longitudeCount; ++longitude)
{
for (latitude = latitudeBegin; latitude < latitudeEnd; ++latitude)
{
float t1 = -PI + longitude * 2 * PI / resol1;
float t2 = -PI + (longitude + 1) * 2 * PI / resol1;
float p1 = -PI / 2 + latitude * 2 * PI / resol2;
float p2 = -PI / 2 + (latitude + 1) * 2 * PI / resol2;
float r0, r1, r2, r3;
r0 = ssFunc(t1, params);
r1 = ssFunc(p1, ¶ms[6]);
r2 = ssFunc(t2, params);
r3 = ssFunc(p2, ¶ms[6]);
if (r0 != 0 && r1 != 0 && r2 != 0 && r3 != 0)
{
VECTOR3 pa, pb, pc, pd;
VECTOR3 v1, v2, n;
float ca;
int i;
superShapeMap(&pa, r0, r1, t1, p1);
superShapeMap(&pb, r2, r1, t2, p1);
superShapeMap(&pc, r2, r3, t2, p2);
superShapeMap(&pd, r0, r3, t1, p2);
if (latitude == latitudeBegin + 1)
pa.z = pb.z = 0;
vector3Sub(&v1, &pb, &pa);
vector3Sub(&v2, &pd, &pa);
n.x = v1.y * v2.z - v1.z * v2.y;
n.y = v1.z * v2.x - v1.x * v2.z;
n.z = v1.x * v2.y - v1.y * v2.x;
ca = pa.z + 0.5f;
for (i = currentVertex * 3;
i < (currentVertex + 6) * 3;
i += 3)
{
result->normalArray[i] = FIXED(n.x);
result->normalArray[i + 1] = FIXED(n.y);
result->normalArray[i + 2] = FIXED(n.z);
}
for (i = currentVertex * 4;
i < (currentVertex + 6) * 4;
i += 4)
{
int a, color[3];
for (a = 0; a < 3; ++a)
{
color[a] = (int)(ca * baseColor[a] * 255);
if (color[a] > 255) color[a] = 255;
}
result->colorArray[i] = (GLubyte)color[0];
result->colorArray[i + 1] = (GLubyte)color[1];
result->colorArray[i + 2] = (GLubyte)color[2];
result->colorArray[i + 3] = 0;
}
result->vertexArray[currentVertex * 3] = FIXED(pa.x);
result->vertexArray[currentVertex * 3 + 1] = FIXED(pa.y);
result->vertexArray[currentVertex * 3 + 2] = FIXED(pa.z);
++currentVertex;
result->vertexArray[currentVertex * 3] = FIXED(pb.x);
result->vertexArray[currentVertex * 3 + 1] = FIXED(pb.y);
result->vertexArray[currentVertex * 3 + 2] = FIXED(pb.z);
++currentVertex;
result->vertexArray[currentVertex * 3] = FIXED(pd.x);
result->vertexArray[currentVertex * 3 + 1] = FIXED(pd.y);
result->vertexArray[currentVertex * 3 + 2] = FIXED(pd.z);
++currentVertex;
result->vertexArray[currentVertex * 3] = FIXED(pb.x);
result->vertexArray[currentVertex * 3 + 1] = FIXED(pb.y);
result->vertexArray[currentVertex * 3 + 2] = FIXED(pb.z);
++currentVertex;
result->vertexArray[currentVertex * 3] = FIXED(pc.x);
result->vertexArray[currentVertex * 3 + 1] = FIXED(pc.y);
result->vertexArray[currentVertex * 3 + 2] = FIXED(pc.z);
++currentVertex;
result->vertexArray[currentVertex * 3] = FIXED(pd.x);
result->vertexArray[currentVertex * 3 + 1] = FIXED(pd.y);
result->vertexArray[currentVertex * 3 + 2] = FIXED(pd.z);
++currentVertex;
}
++currentQuad;
}
}
result->count = currentVertex;
return result;
}
