mrkd
2/29/2012 - 5:14 AM
transform.cpp
transform.cpp
/*
*Skeleton transform program
* SEIS750
* Spring 2012
**/
#include <GL/Angel.h>
#include <math.h>
#pragma comment(lib, "glew32.lib")
//store window width and height
int ww=500, wh=500;
#define M_PI 3.14159265358979323846
float tx = 1.0;
float ty = 1.0;
float tz = 1.0;
float cube2tx = 1.0;
float cube2ty = 1.0;
float cube2tz = 1.0;
float rx = 0.0;
float ry = 0.0;
float rz = 0.0;
GLuint vao[2];
GLuint vbo[4];
//our modelview and perspective matrices
mat4 mv, p;
//and we'll need pointers to our shader variables
GLuint model_view;
GLuint projection;
GLuint vPosition;
GLuint vColor;
vec4 cubeVerts[36];
vec4 cubeColors[36];
vec4 stageVerts[9];
vec4 stageColors[9];
void key_press (unsigned char key, int x, int y);
void special_key_press (int key, int x, int y);
void my_timer(int v);
void my_timer (int v)
{
cube2ty += 1.0;
cube2tx += 1.0;
glutPostRedisplay();
glutTimerFunc(1000/v, my_timer, v);
}
void generateCube(){
for(int i=0; i<6; i++){
cubeColors[i] = vec4(0.0, 1.0, 1.0, 1.0); //front
}
cubeVerts[0] = vec4(1.0f, -1.0f, 1.0f, 1.0);
cubeVerts[1] = vec4(1.0f, 1.0f, 1.0f, 1.0);
cubeVerts[2] = vec4(-1.0f, 1.0f, 1.0f, 1.0);
cubeVerts[3] = vec4(-1.0f, 1.0f, 1.0f, 1.0);
cubeVerts[4] = vec4(-1.0f, -1.0f, 1.0f, 1.0);
cubeVerts[5] = vec4(1.0f, -1.0f, 1.0f, 1.0);
for(int i=6; i<12; i++){
cubeColors[i] = vec4(1.0, 0.0, 1.0, 1.0); //back
}
cubeVerts[6] = vec4(-1.0f, -1.0f, -1.0f, 1.0);
cubeVerts[7] = vec4(-1.0f, 1.0f, -1.0f, 1.0);
cubeVerts[8] = vec4(1.0f, 1.0f, -1.0f, 1.0);
cubeVerts[9] = vec4(1.0f, 1.0f, -1.0f, 1.0);
cubeVerts[10] = vec4(1.0f, -1.0f, -1.0f, 1.0);
cubeVerts[11] = vec4(-1.0f, -1.0f, -1.0f, 1.0);
for(int i=12; i<18; i++){
cubeColors[i] = vec4(1.0, 1.0, 0.0, 1.0); //left
}
cubeVerts[12] = vec4(1.0f, 1.0f, 1.0f, 1.0);
cubeVerts[13] = vec4(1.0f, -1.0f, 1.0f, 1.0);
cubeVerts[14] = vec4(1.0f, -1.0f, -1.0f, 1.0);
cubeVerts[15] = vec4(1.0f, -1.0f, -1.0f, 1.0);
cubeVerts[16] = vec4(1.0f, 1.0f, -1.0f, 1.0);
cubeVerts[17] = vec4(1.0f, 1.0f, 1.0f, 1.0);
for(int i=18; i<24; i++){
cubeColors[i] = vec4(1.0, 0.0, 0.0, 1.0); //right
}
cubeVerts[18] = vec4(-1.0f, 1.0f, -1.0f, 1.0);
cubeVerts[19] = vec4(-1.0f, -1.0f, -1.0f, 1.0);
cubeVerts[20] = vec4(-1.0f, -1.0f, 1.0f, 1.0);
cubeVerts[21] = vec4(-1.0f, -1.0f, 1.0f, 1.0);
cubeVerts[22] = vec4(-1.0f, 1.0f, 1.0f, 1.0);
cubeVerts[23] = vec4(-1.0f, 1.0f, -1.0f, 1.0);
for(int i=24; i<30; i++){
cubeColors[i] = vec4(0.0, 0.0, 1.0, 1.0); //top
}
cubeVerts[24] = vec4(1.0f, 1.0f, 1.0f, 1.0);
cubeVerts[25] = vec4(1.0f, 1.0f, -1.0f, 1.0);
cubeVerts[26] = vec4(-1.0f, 1.0f, -1.0f, 1.0);
cubeVerts[27] = vec4(-1.0f, 1.0f, -1.0f, 1.0);
cubeVerts[28] = vec4(-1.0f, 1.0f, 1.0f, 1.0);
cubeVerts[29] = vec4(1.0f, 1.0f, 1.0f, 1.0);
for(int i=30; i<36; i++){
cubeColors[i] = vec4(0.0, 1.0, 0.0, 1.0); //bottom
}
cubeVerts[30] = vec4(1.0f, -1.0f, -1.0f, 1.0);
cubeVerts[31] = vec4(1.0f, -1.0f, 1.0f, 1.0);
cubeVerts[32] = vec4(-1.0f, -1.0f, 1.0f, 1.0);
cubeVerts[33] = vec4(-1.0f, -1.0f, 1.0f, 1.0);
cubeVerts[34] = vec4(-1.0f, -1.0f, -1.0f, 1.0);
cubeVerts[35] = vec4(1.0f, -1.0f, -1.0f, 1.0);
}
void generateStage() {
for(int i=0; i<6; i++){
stageColors[i] = vec4(0.0, 1.0, 1.0, 1.0); //front
}
stageVerts[0] = vec4(10.0f, 0.0f, -10.0f, 1.0);
stageVerts[1] = vec4(10.0f, 0.0f, 10.0f, 1.0);
stageVerts[2] = vec4(-10.0f, 0.0f, 10.0f, 1.0);
stageVerts[3] = vec4(-10.0f, 0.0f, 10.0f, 1.0);
stageVerts[4] = vec4(-10.0f, 0.0f, -10.0f, 1.0);
stageVerts[5] = vec4(10.0f, 0.0f, -1.0f, 1.0);
}
void display(void)
{
/*clear all pixels*/
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// we'll explain this later, but it's setting our default modelview matrix
mv = LookAt(vec4(0, 0, 20, 1.0), vec4(0, 0, 0, 1.0), vec4(0, 1, 0, 0.0));
// any additional modelview transformations would happen here
/* Rotation */
mv = mv*RotateX(rx);
mv = mv*RotateY(ry);
mv = mv*RotateZ(rz);
/* Translation */
mv = mv*Translate(tx,ty,tz);
// now that our modelview matrix is all set to go, we send it to our shaders
// modelview is the same for all vertices in an object, so it's a uniform rather
// than an attribute
glUniformMatrix4fv(model_view, 1, GL_TRUE, mv);
// and we also need to send our projection matrix, which again is more appropriately
// a uniform instead of an attribute since it's the same for every vertex
glUniformMatrix4fv(projection, 1, GL_TRUE, p);
// Now we have a vertex array that has all of our cube vertex locations and colors
glBindVertexArray( vao[0] );
glDrawArrays( GL_TRIANGLES, 0, 36 ); // draw the cube
/***************/
/* SECOND CUBE */
/***************/
// we'll explain this later, but it's setting our default modelview matrix
mv = LookAt(vec4(0, 0, 20, 1.0), vec4(0, 0, 0, 1.0), vec4(0, 1, 0, 0.0));
/* ROTATION */
mv = mv*RotateY(cube2ty);
mv = mv*RotateX(cube2tx);
/* TRANSLATE */
mv = mv*Translate(5,1.0,1.0);
// now that our modelview matrix is all set to go, we send it to our shaders
// modelview is the same for all vertices in an object, so it's a uniform rather
// than an attribute
glUniformMatrix4fv(model_view, 1, GL_TRUE, mv);
// and we also need to send our projection matrix, which again is more appropriately
// a uniform instead of an attribute since it's the same for every vertex
glUniformMatrix4fv(projection, 1, GL_TRUE, p);
// Now we have a vertex array that has all of our cube vertex locations and colors
// already bound so dont have to rebind - glBindVertexArray( vao[0] );
glDrawArrays( GL_TRIANGLES, 0, 36 ); // draw the cube
/*start processing buffered OpenGL routines*/
glutSwapBuffers();
}
void Keyboard(unsigned char key, int x, int y) {
/*exit when the escape key is pressed*/
if (key == 27)
exit(0);
switch(key)
{
case 'a':
tz +=1;
break;
case 'z':
tz-=1;
break;
case 'r':
rx += 10;
printf("rotate angle: %f\n", rx);
break;
case 'f':
rx-=10;
break;
case 'g':
ry-=10;
break;
case 'h':
rz-=10;
break;
case 't':
ry += 10;
break;
case 'y':
rz += 10;
break;
}
glutPostRedisplay();
}
void special_key_press (int key, int x, int y)
{
switch(key)
{
case GLUT_KEY_UP:
tx+=1;
break;
case GLUT_KEY_DOWN:
tx-=1;
break;
case GLUT_KEY_RIGHT:
ty+=1;
break;
case GLUT_KEY_LEFT:
ty-=1;
break;
}
glutPostRedisplay();
}
void init() {
/*select clearing (background) color*/
glClearColor(0.0, 0.0, 0.0, 0.0);
//populate our arrays
generateCube();
generateStage();
// Load shaders and use the resulting shader program
GLuint program = InitShader( "vshader-transform.glsl", "fshader-transform.glsl" );
glUseProgram( program );
// Create a vertex array object
glGenVertexArrays( 1, &vao[0] );
// Create and initialize any buffer objects
glBindVertexArray( vao[0] );
glGenBuffers( 2, &vbo[0] );
glBindBuffer( GL_ARRAY_BUFFER, vbo[0] );
glBufferData( GL_ARRAY_BUFFER, sizeof(cubeVerts), cubeVerts, GL_STATIC_DRAW);
// notice that since position is unique for every vertex, we treat it as an
// attribute instead of a uniform
vPosition = glGetAttribLocation(program, "vPosition");
glEnableVertexAttribArray(vPosition);
glVertexAttribPointer(vPosition, 4, GL_FLOAT, GL_FALSE, 0, 0);
//and now our colors for each vertex
glBindBuffer( GL_ARRAY_BUFFER, vbo[1] );
glBufferData( GL_ARRAY_BUFFER, sizeof(cubeColors), cubeColors, GL_STATIC_DRAW );
vColor = glGetAttribLocation(program, "vColor");
glEnableVertexAttribArray(vColor);
glVertexAttribPointer(vColor, 4, GL_FLOAT, GL_FALSE, 0, 0);
//grab pointers for our modelview and perspecive uniform matrices
model_view = glGetUniformLocation(program, "model_view");
projection = glGetUniformLocation(program, "projection");
//Only draw the things in the front layer
glEnable(GL_DEPTH_TEST);
}
void reshape(int width, int height){
ww= width;
wh = height;
//field of view angle, aspect ratio, closest distance from camera to object, largest distanec from camera to object
p = Perspective(45.0, (float)width/(float)height, 1.0, 100.0);
glViewport( 0, 0, width, height );
}
int main(int argc, char **argv)
{
/*set up window for display*/
glutInit(&argc, argv);
glutInitWindowPosition(0, 0);
glutInitWindowSize(ww, wh);
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
glutCreateWindow("Transformations Exercise");
glewExperimental = GL_TRUE;
glewInit();
init();
glutDisplayFunc(display);
glutKeyboardFunc(Keyboard);
glutSpecialFunc(special_key_press);
glutReshapeFunc(reshape);
glutTimerFunc(500,my_timer,60);
//glutIdleFunc(idle);
glutMainLoop();
return 0;
}