void InitGL() {
glClearColor(1,1,1,1);
glGenQueries(1, &query);
glGenQueries(1, &t_query);
texture_size_x = numX+1;
texture_size_y = numY+1;
CHECK_GL_ERRORS
startTime = (float)glutGet(GLUT_ELAPSED_TIME);
// get ticks per second
QueryPerformanceFrequency(&frequency);
// start timer
QueryPerformanceCounter(&t1);
size_t i=0, j=0, count=0;
int l1=0, l2=0;
int v = numY+1;
int u = numX+1;
printf("Total triangles: %3d\n",numX*numY*2);
indices.resize( numX*numY*2*3);
X.resize(total_points);
X_last.resize(total_points);
F.resize(total_points);
//fill in positions
for(int j=0;j<=numY;j++) {
for(int i=0;i<=numX;i++) {
X[count] = glm::vec4( ((float(i)/(u-1)) *2-1)* hsize, sizeX+1, ((float(j)/(v-1) )* sizeY),1);
X_last[count] = X[count];
count++;
}
}
//fill in indices
GLushort* id=&indices[0];
for (int i = 0; i < numY; i++) {
for (int j = 0; j < numX; j++) {
int i0 = i * (numX+1) + j;
int i1 = i0 + 1;
int i2 = i0 + (numX+1);
int i3 = i2 + 1;
if ((j+i)%2) {
*id++ = i0; *id++ = i2; *id++ = i1;
*id++ = i1; *id++ = i2; *id++ = i3;
} else {
*id++ = i0; *id++ = i2; *id++ = i3;
*id++ = i0; *id++ = i3; *id++ = i1;
}
}
}
glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
glEnable(GL_CULL_FACE);
glEnable(GL_LINE_SMOOTH);
glHint(GL_LINE_SMOOTH_HINT, GL_NICEST);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glCullFace(GL_BACK);
glEnable(GL_VERTEX_PROGRAM_POINT_SIZE);
//Disable vsync
wglSwapIntervalEXT(0);
// Setup springs
// Horizontal
for (l1 = 0; l1 < v; l1++) // v
for (l2 = 0; l2 < (u - 1); l2++) {
AddSpring((l1 * u) + l2,(l1 * u) + l2 + 1,KsStruct,KdStruct);
}
// Vertical
for (l1 = 0; l1 < (u); l1++)
for (l2 = 0; l2 < (v - 1); l2++) {
AddSpring((l2 * u) + l1,((l2 + 1) * u) + l1,KsStruct,KdStruct);
}
// Shearing Springs
for (l1 = 0; l1 < (v - 1); l1++)
for (l2 = 0; l2 < (u - 1); l2++) {
AddSpring((l1 * u) + l2,((l1 + 1) * u) + l2 + 1,KsShear,KdShear);
AddSpring(((l1 + 1) * u) + l2,(l1 * u) + l2 + 1,KsShear,KdShear);
}
// Bend Springs
for (l1 = 0; l1 < (v); l1++) {
for (l2 = 0; l2 < (u - 2); l2++) {
AddSpring((l1 * u) + l2,(l1 * u) + l2 + 2,KsBend,KdBend);
}
AddSpring((l1 * u) + (u - 3),(l1 * u) + (u - 1),KsBend,KdBend);
}
for (l1 = 0; l1 < (u); l1++) {
for (l2 = 0; l2 < (v - 2); l2++) {
AddSpring((l2 * u) + l1,((l2 + 2) * u) + l1,KsBend,KdBend);
}
AddSpring(((v - 3) * u) + l1,((v - 1) * u) + l1,KsBend,KdBend);
}
massSpringShader.LoadFromFile(GL_VERTEX_SHADER, "shaders/Spring.vp");
particleShader.LoadFromFile(GL_VERTEX_SHADER,"shaders/Basic.vp");
particleShader.LoadFromFile(GL_FRAGMENT_SHADER,"shaders/Basic.fp");
renderShader.LoadFromFile(GL_VERTEX_SHADER,"shaders/Passthrough.vp");
renderShader.LoadFromFile(GL_FRAGMENT_SHADER,"shaders/Passthrough.fp");
massSpringShader.CreateAndLinkProgram();
massSpringShader.Use();
massSpringShader.AddAttribute("position_mass");
massSpringShader.AddAttribute("prev_position");
massSpringShader.AddUniform("tex_position_mass");
massSpringShader.AddUniform("tex_pre_position_mass");
massSpringShader.AddUniform("MVP");
massSpringShader.AddUniform("dt");
massSpringShader.AddUniform("gravity");
massSpringShader.AddUniform("ksStr");
massSpringShader.AddUniform("ksShr");
massSpringShader.AddUniform("ksBnd");
massSpringShader.AddUniform("kdStr");
massSpringShader.AddUniform("kdShr");
massSpringShader.AddUniform("kdBnd");
massSpringShader.AddUniform("DEFAULT_DAMPING");
massSpringShader.AddUniform("texsize_x");
massSpringShader.AddUniform("texsize_y");
massSpringShader.AddUniform("step");
massSpringShader.AddUniform("inv_cloth_size");
massSpringShader.AddUniform("ellipsoid");
glUniform1i(massSpringShader("tex_position_mass"), 0);
glUniform1i(massSpringShader("tex_pre_position_mass"), 1);
massSpringShader.UnUse();
CHECK_GL_ERRORS
particleShader.CreateAndLinkProgram();
particleShader.Use();
particleShader.AddAttribute("position_mass");
particleShader.AddUniform("pointSize");
particleShader.AddUniform("MV");
particleShader.AddUniform("MVP");
particleShader.AddUniform("vColor");
particleShader.AddUniform("selected_index");
glUniform1f(particleShader("pointSize"), pointSize);
glUniform4fv(particleShader("vColor"),1, vRed);
particleShader.UnUse();
renderShader.CreateAndLinkProgram();
renderShader.Use();
renderShader.AddAttribute("position_mass");
renderShader.AddUniform("MVP");
renderShader.AddUniform("vColor");
glUniform4fv(renderShader("vColor"),1, vGray);
renderShader.UnUse();
CHECK_GL_ERRORS
//create vbo
createVBO();
//setup transform feedback attributes
glGenTransformFeedbacks(1, &tfID);
glBindTransformFeedback(GL_TRANSFORM_FEEDBACK, tfID);
const char* varying_names[]={"out_position_mass", "out_prev_position"};
glTransformFeedbackVaryings(massSpringShader.GetProgram(), 2, varying_names, GL_SEPARATE_ATTRIBS);
glLinkProgram(massSpringShader.GetProgram());
}
//initialize OpenGL
void InitGL() {
//set the background colour to white
glClearColor(1,1,1,1);
//generate hardware query objects
glGenQueries(1, &query);
glGenQueries(1, &t_query);
//setup texture size for shaders
texture_size_x = numX+1;
texture_size_y = numY+1;
CHECK_GL_ERRORS
//get initial time
startTime = (float)glutGet(GLUT_ELAPSED_TIME);
// get ticks per second
QueryPerformanceFrequency(&frequency);
// start timer
QueryPerformanceCounter(&t1);
//local variables
size_t i=0, j=0, count=0;
int l1=0, l2=0;
int v = numY+1;
int u = numX+1;
printf("Total triangles: %3d\n",numX*numY*2);
//resize the cloth indices, position, previous position and force vectors
indices.resize( numX*numY*2*3);
X.resize(total_points);
X_last.resize(total_points);
F.resize(total_points);
//fill in positions
for(int j=0;j<=numY;j++) {
for(int i=0;i<=numX;i++) {
X[count] = glm::vec4( ((float(i)/(u-1)) *2-1)* hsize, sizeX+1, ((float(j)/(v-1) )* sizeY),1);
X_last[count] = X[count];
count++;
}
}
//fill in indices
GLushort* id=&indices[0];
for (int i = 0; i < numY; i++) {
for (int j = 0; j < numX; j++) {
int i0 = i * (numX+1) + j;
int i1 = i0 + 1;
int i2 = i0 + (numX+1);
int i3 = i2 + 1;
if ((j+i)%2) {
*id++ = i0; *id++ = i2; *id++ = i1;
*id++ = i1; *id++ = i2; *id++ = i3;
} else {
*id++ = i0; *id++ = i2; *id++ = i3;
*id++ = i0; *id++ = i3; *id++ = i1;
}
}
}
//set the polygon rendering to render them as lines
glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
//enable back face culling
glEnable(GL_CULL_FACE);
glCullFace(GL_BACK);
//set smooth line rendering
glEnable(GL_LINE_SMOOTH);
glHint(GL_LINE_SMOOTH_HINT, GL_NICEST);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
//enable state to use the vertex shader to reset the particle size
//by writing to gl_PointSize value
glEnable(GL_VERTEX_PROGRAM_POINT_SIZE);
// Setup springs
// Horizontal
for (l1 = 0; l1 < v; l1++) // v
for (l2 = 0; l2 < (u - 1); l2++) {
AddSpring((l1 * u) + l2,(l1 * u) + l2 + 1,KsStruct,KdStruct);
}
// Vertical
for (l1 = 0; l1 < (u); l1++)
for (l2 = 0; l2 < (v - 1); l2++) {
AddSpring((l2 * u) + l1,((l2 + 1) * u) + l1,KsStruct,KdStruct);
}
// Shearing Springs
for (l1 = 0; l1 < (v - 1); l1++)
for (l2 = 0; l2 < (u - 1); l2++) {
AddSpring((l1 * u) + l2,((l1 + 1) * u) + l2 + 1,KsShear,KdShear);
AddSpring(((l1 + 1) * u) + l2,(l1 * u) + l2 + 1,KsShear,KdShear);
}
// Bend Springs
for (l1 = 0; l1 < (v); l1++) {
for (l2 = 0; l2 < (u - 2); l2++) {
AddSpring((l1 * u) + l2,(l1 * u) + l2 + 2,KsBend,KdBend);
}
AddSpring((l1 * u) + (u - 3),(l1 * u) + (u - 1),KsBend,KdBend);
}
for (l1 = 0; l1 < (u); l1++) {
for (l2 = 0; l2 < (v - 2); l2++) {
AddSpring((l2 * u) + l1,((l2 + 2) * u) + l1,KsBend,KdBend);
}
AddSpring(((v - 3) * u) + l1,((v - 1) * u) + l1,KsBend,KdBend);
}
//setup shader loading
massSpringShader.LoadFromFile(GL_VERTEX_SHADER, "shaders/Spring.vert");
particleShader.LoadFromFile(GL_VERTEX_SHADER,"shaders/Basic.vert");
particleShader.LoadFromFile(GL_FRAGMENT_SHADER,"shaders/Basic.frag");
renderShader.LoadFromFile(GL_VERTEX_SHADER,"shaders/Passthrough.vert");
renderShader.LoadFromFile(GL_FRAGMENT_SHADER,"shaders/Passthrough.frag");
//compile and link mass spring shader
massSpringShader.CreateAndLinkProgram();
massSpringShader.Use();
//add attributes and uniforms
massSpringShader.AddAttribute("position_mass");
massSpringShader.AddAttribute("prev_position");
massSpringShader.AddUniform("tex_position_mass");
massSpringShader.AddUniform("tex_pre_position_mass");
massSpringShader.AddUniform("MVP");
massSpringShader.AddUniform("dt");
massSpringShader.AddUniform("gravity");
massSpringShader.AddUniform("ksStr");
massSpringShader.AddUniform("ksShr");
massSpringShader.AddUniform("ksBnd");
massSpringShader.AddUniform("kdStr");
massSpringShader.AddUniform("kdShr");
massSpringShader.AddUniform("kdBnd");
massSpringShader.AddUniform("DEFAULT_DAMPING");
massSpringShader.AddUniform("texsize_x");
massSpringShader.AddUniform("texsize_y");
massSpringShader.AddUniform("step");
massSpringShader.AddUniform("inv_cloth_size");
massSpringShader.AddUniform("ellipsoid_xform");
massSpringShader.AddUniform("inv_ellipsoid");
massSpringShader.AddUniform("ellipsoid");
massSpringShader.UnUse();
CHECK_GL_ERRORS
//compile and link particle shader
particleShader.CreateAndLinkProgram();
particleShader.Use();
//setup attributes and uniforms
particleShader.AddAttribute("position_mass");
particleShader.AddUniform("pointSize");
particleShader.AddUniform("MV");
particleShader.AddUniform("MVP");
particleShader.AddUniform("vColor");
particleShader.AddUniform("selected_index");
//pass values to contant uniforms
glUniform1f(particleShader("pointSize"), pointSize);
glUniform4fv(particleShader("vColor"),1, vRed);
particleShader.UnUse();
//compile and link render shader
renderShader.CreateAndLinkProgram();
renderShader.Use();
//setup attributes and uniforms
renderShader.AddAttribute("position_mass");
renderShader.AddUniform("MVP");
renderShader.AddUniform("vColor");
//pass values to constant uniforms
glUniform4fv(renderShader("vColor"),1, vGray);
renderShader.UnUse();
CHECK_GL_ERRORS
//create vbo
createVBO();
//collision ellipsoid
ellipsoid = glm::translate(glm::mat4(1),glm::vec3(0,2,0));
ellipsoid = glm::rotate(ellipsoid, 45.0f ,glm::vec3(1,0,0));
ellipsoid = glm::scale(ellipsoid, glm::vec3(fRadius,fRadius,fRadius/2));
inverse_ellipsoid = glm::inverse(ellipsoid);
//setup transform feedback attributes
glGenTransformFeedbacks(1, &tfID);
glBindTransformFeedback(GL_TRANSFORM_FEEDBACK, tfID);
//pass the vertex shader outputs for transform feedback
const char* varying_names[]={"out_position_mass", "out_prev_position"};
glTransformFeedbackVaryings(massSpringShader.GetProgram(), 2, varying_names, GL_SEPARATE_ATTRIBS);
//relink the massSpringShader program
glLinkProgram(massSpringShader.GetProgram());
//set the mass spring shader and pass values to constant uniforms
massSpringShader.Use();
glUniform1f(massSpringShader("dt"), timeStep);
glUniform3fv(massSpringShader("gravity"),1,&gravity.x);
glUniform1i(massSpringShader("tex_position_mass"), 0);
glUniform1i(massSpringShader("tex_pre_position_mass"), 1);
glUniform1i(massSpringShader("texsize_x"),texture_size_x);
glUniform1i(massSpringShader("texsize_y"),texture_size_y);
glUniformMatrix4fv(massSpringShader("ellipsoid_xform"), 1, GL_FALSE, glm::value_ptr(ellipsoid));
glUniformMatrix4fv(massSpringShader("inv_ellipsoid"), 1, GL_FALSE, glm::value_ptr(inverse_ellipsoid));
glUniform4f(massSpringShader("ellipsoid"),0, 0, 0, fRadius);
glUniform2f(massSpringShader("inv_cloth_size"),float(sizeX)/numX,float(sizeY)/numY);
glUniform2f(massSpringShader("step"),1.0f/(texture_size_x-1.0f),1.0f/(texture_size_y-1.0f));
glUniform1f(massSpringShader("ksStr"), KsStruct);
glUniform1f(massSpringShader("ksShr"), KsShear);
glUniform1f(massSpringShader("ksBnd"), KsBend);
glUniform1f(massSpringShader("kdStr"), KdStruct/1000.0f);
glUniform1f(massSpringShader("kdShr"), KdShear/1000.0f);
glUniform1f(massSpringShader("kdBnd"), KdBend/1000.0f);
glUniform1f(massSpringShader("DEFAULT_DAMPING"), DEFAULT_DAMPING);
massSpringShader.UnUse();
//disable vsync
wglSwapIntervalEXT(0);
}
