void spline_mesh(void){
static GLboolean first = GL_TRUE;
static GLuint vertBuffer;
static GLuint normalBuffer;
static GLuint indexBuffer;
GLdouble tube[TUBE_N][TUBE_M][3];
GLdouble tubeNormals[TUBE_N][TUBE_M][3];
if(first){
double t, u;
int i, j, k;
double dt = 2 * M_PI / TUBE_N;
double du = 2 * M_PI / TUBE_M;
for(i = 0, t = 0.0; i < TUBE_N; i++, t += dt){
GLdouble x = (a + b * cos(q * t)) * cos(p * t);
GLdouble y = (a + b * cos(q * t)) * sin(p * t);
GLdouble z = b * sin(q * t);
GLdouble tangx = -p * y - b * q * sin(q * t) * cos(p * t);
GLdouble tangy = p * x - b * q * sin(q * t) * sin(p * t);
GLdouble tangz = b * q * cos(q * t);
GLdouble accelx = -p * tangy + b * q * (p * sin(q * t) * sin(p * t) - q * cos(q * t) * cos(p * t));
GLdouble accely = p * tangx - b * q * (p * sin(q * t) * cos(p * t) + q * cos(q * t) * sin(p * t));
GLdouble accelz = -(q * q) * b * sin(q * t);
GLdouble C[3] = {x, y, z};
GLdouble T[3] = {tangx, tangy, tangz};
GLdouble A[3] = {accelx, accely, accelz};
GLdouble N[3];
GLdouble B[3];
cross(T, A, B);
normalize(T);
normalize(B);
cross(B, T, N);
for(j = 0, u = 0.0; j < TUBE_M; j++, u += du){
for(k = 0; k < 3; k++){
tubeNormals[i][j][k] = cos(u) * B[k] + sin(u) * N[k];
tube[i][j][k] = C[k] + R * tubeNormals[i][j][k];
}
}
}
createMeshStripIndices();
glGenBuffers(1, &indexBuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBuffer);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(tubeStrips), tubeStrips, GL_STATIC_DRAW);
glGenBuffers(1, &vertBuffer);
glBindBuffer(GL_ARRAY_BUFFER, vertBuffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(tube), tube, GL_STATIC_DRAW);
glGenBuffers(1, &normalBuffer);
glBindBuffer(GL_ARRAY_BUFFER, normalBuffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(tubeNormals), tubeNormals, GL_STATIC_DRAW);
first = GL_FALSE;
}
loadUniforms();
glEnableVertexAttribArray(vertexPositionAttr);
glBindBuffer(GL_ARRAY_BUFFER, vertBuffer);
glVertexAttribPointer(vertexPositionAttr, 3, GL_DOUBLE, GL_FALSE, 0, (GLvoid*) 0);
//glEnableVertexAttribArray(vertexNormalAttr);
//glBindBuffer(GL_ARRAY_BUFFER, normalBuffer);
//glVertexAttribPointer(vertexNormalAttr, 3, GL_DOUBLE, GL_FALSE, 0, (GLvoid*) 0);
int i;
char *offset;
glBindBuffer(GL_ARRAY_BUFFER, vertBuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBuffer);
for(i = 0, offset = 0; i < NUM_STRIPS; i++, offset += INDICES_PER_STRIP * sizeof(GLushort)){
glDrawElements(GL_QUAD_STRIP, INDICES_PER_STRIP, GL_UNSIGNED_SHORT, (GLvoid*) offset);
}
}
void ellipsoidWireFrame() {
static GLuint vertBuffer;
static GLuint normalsBuffer;
static GLuint indexBuffer;
static GLboolean first = GL_TRUE;
GLfloat u,v;
int m,n;
int cnt=0;
if (first || changeFlag) {
for (n=0; n <= BIG_N; n++) {
v = -M_PI/2.0 + (float) n/ (float) BIG_N * M_PI;
for (m=0; m <= BIG_M; m++) {
u = -M_PI + (float) m/ (float) BIG_M * 2.0 * M_PI;
verticesArray[cnt] = xValue(u,v);
normalsArray[cnt] = nxValue(u,v);
cnt++;
verticesArray[cnt] = yValue(u,v);
normalsArray[cnt] = nyValue(u,v);
cnt++;
verticesArray[cnt] = zValue(u,v);
normalsArray[cnt] = nzValue(u,v);
cnt++;
}
}
glGenBuffers(1, &vertBuffer);
glBindBuffer(GL_ARRAY_BUFFER, vertBuffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(verticesArray),
verticesArray, GL_STATIC_DRAW);
glGenBuffers(1, &normalsBuffer);
glBindBuffer(GL_ARRAY_BUFFER,normalsBuffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(normalsArray),
normalsArray, GL_STATIC_DRAW);
if (first) {
createMeshStripIndices();
glGenBuffers(1, &indexBuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBuffer);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(tubeStrips),
tubeStrips, GL_STATIC_DRAW);
}
first = GL_FALSE;
changeFlag = GL_FALSE;
}
loadUniforms();
glEnableVertexAttribArray(vertexPositionAttr);
glBindBuffer(GL_ARRAY_BUFFER, vertBuffer);
glVertexAttribPointer(vertexPositionAttr,3, GL_FLOAT,GL_FALSE, 0, (GLvoid*) 0);
glBindBuffer(GL_ARRAY_BUFFER, normalsBuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER,indexBuffer);
glDrawElements(GL_QUAD_STRIP, TOTAL_INDICES, GL_UNSIGNED_SHORT, (GLvoid*) 0);
}
