computer-grafik-1/u05-2/main.c

397 lines
9.6 KiB
C

#include <stdio.h>
#include <GL/glew.h>
#include <GLFW/glfw3.h>
#include "vertexShader.c"
#include "fragmentShader.c"
#include "matrixMath.h"
#include "transformation.h"
#include <stdlib.h>
#include <math.h>
#include <string.h>
#include <stdbool.h>
#define RESTART 345678
GLuint program;
GLuint vao;
GLuint cubeIndicesBufferObject;
bool exitRequested = false;
GLFWwindow* window;
GLfloat aspectRatio = 1.0f;
GLfloat step = 0.0f;
const GLfloat pi = 3.14159f;
GLfloat cameraPosition[3] = {0.0f, 0.0f, 2.0f};
GLfloat cube[] = {
1.0f, 1.0f, 1.0f,
1.0f, 1.0f, -1.0f,
1.0f, -1.0f, 1.0f,
1.0f, -1.0f, -1.0f,
-1.0f, 1.0f, 1.0f,
-1.0f, 1.0f, -1.0f,
-1.0f, -1.0f, 1.0f,
-1.0f, -1.0f, -1.0f
};
GLfloat ground[] = {
1.0f, 0.0f, 1.0f,
1.0f, 0.0f, -1.0f,
-1.0f, 0.0f, 0.0f,
-1.0f, 0.0f, -1.0f
};
GLuint cubeIndices[] = {
0, 1, 2,
1, 3, 2,
1, 7, 3,
1, 5, 7,
4, 6, 5,
5, 6, 7,
0, 2, 4,
4, 2, 6,
7, 6, 3,
6, 2, 3,
4, 5, 1,
4, 1, 0
};
GLuint groundIndices[] = {
0, 1, 2,
1, 3, 2
};
void handleInputs(void) {
if (glfwGetKey(window, GLFW_KEY_S) == GLFW_PRESS) {
cameraPosition[2] += 0.02f;
}
if (glfwGetKey(window, GLFW_KEY_W) == GLFW_PRESS) {
cameraPosition[2] -= 0.02f;
}
if (glfwGetKey(window, GLFW_KEY_SPACE) == GLFW_PRESS) {
cameraPosition[1] += 0.02f;
}
if (glfwGetKey(window, GLFW_KEY_LEFT_SHIFT) == GLFW_PRESS) {
cameraPosition[1] -= 0.02f;
}
}
void keyboardHandler(GLFWwindow* window, int key, int scancode, int action, int mods) {
if (action == GLFW_PRESS) {
if (key == GLFW_KEY_ESCAPE) {
exitRequested = true;
}
}
}
void init(void) {
// create and compile vertex shader
const GLchar *vertexTextConst = vertexShader_glsl;
GLuint vertexShader = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(vertexShader, 1, &vertexTextConst, &vertexShader_glsl_len);
glCompileShader(vertexShader);
GLint status;
glGetShaderiv(vertexShader, GL_COMPILE_STATUS, &status);
if (!status) {
printf("Error compiling vertex shader: ");
GLchar infoLog[1024];
glGetShaderInfoLog(vertexShader, 1024, NULL, infoLog);
printf("%s",infoLog);
}
vertexTextConst = NULL;
// create and compile fragment shader
const GLchar *fragmentTextConst = fragmentShader_glsl;
GLuint fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(fragmentShader, 1, &fragmentTextConst, &fragmentShader_glsl_len);
glCompileShader(fragmentShader);
glGetShaderiv(fragmentShader, GL_COMPILE_STATUS, &status);
if (!status) {
printf("Error compiling fragment shader: ");
GLchar infoLog[1024];
glGetShaderInfoLog(fragmentShader, 1024, NULL, infoLog);
printf("%s",infoLog);
}
// create and link shader program
program = glCreateProgram();
glAttachShader(program, vertexShader);
glAttachShader(program, fragmentShader);
glLinkProgram(program);
glGetProgramiv(program, GL_LINK_STATUS, &status);
if (!status) {
printf("Error linking program: ");
GLchar infoLog[1024];
glGetProgramInfoLog(program, 1024, NULL, infoLog);
printf("%s",infoLog);
}
glValidateProgram(program);
glGetProgramiv(program, GL_VALIDATE_STATUS, &status);
if (!status) {
printf("Error validating program: ");
GLchar infoLog[1024];
glGetProgramInfoLog(program, 1024, NULL, infoLog);
printf("%s",infoLog);
}
GLuint triangleVertexBufferObject;
glGenBuffers(1, &triangleVertexBufferObject);
glBindBuffer(GL_ARRAY_BUFFER, triangleVertexBufferObject);
glBufferData(GL_ARRAY_BUFFER, sizeof(cube), cube, GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, 0);
// create vertex array object
glGenVertexArrays(1, &vao);
glBindVertexArray(vao);
glBindBuffer(GL_ARRAY_BUFFER, triangleVertexBufferObject);
glVertexAttribPointer(
0,
3,
GL_FLOAT,
GL_FALSE,
sizeof(GLfloat) * 3,
0
);
glEnableVertexAttribArray(0);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindVertexArray(0);
// ENABLE BACKFACE CULLING
glFrontFace(GL_CW);
glEnable(GL_CULL_FACE);
// ENABLE RESTARTING
glEnable(GL_PRIMITIVE_RESTART);
glPrimitiveRestartIndex(RESTART);
// DEFINE INDEX ARRAY FOR ELEMENT DRAWING
glGenBuffers(1, &cubeIndicesBufferObject);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, cubeIndicesBufferObject);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(cubeIndices), cubeIndices, GL_STATIC_DRAW);
glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
}
void drawCube(GLfloat* position, GLfloat* scaleVec, GLfloat* rotateVec) {
GLfloat modelTransformation[16];
identity(modelTransformation);
scale(modelTransformation, modelTransformation, scaleVec);
rotateX(modelTransformation, modelTransformation, rotateVec[0]);
rotateY(modelTransformation, modelTransformation, rotateVec[1]);
rotateZ(modelTransformation, modelTransformation, rotateVec[2]);
translate(modelTransformation, modelTransformation, position);
glUniformMatrix4fv(glGetUniformLocation(program, "modelTransformation"), 1, GL_FALSE, modelTransformation);
glUniform3f(glGetUniformLocation(program, "color"), 1.0f, 0.0f, 0.0f);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, (void*)(0 * sizeof(GLuint)));
glUniform3f(glGetUniformLocation(program, "color"), 1.0f, 1.0f, 0.0f);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, (void*)(6 * sizeof(GLuint)));
glUniform3f(glGetUniformLocation(program, "color"), 1.0f, 1.0f, 1.0f);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, (void*)(12 * sizeof(GLuint)));
glUniform3f(glGetUniformLocation(program, "color"), 0.0f, 1.0f, 1.0f);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, (void*)(18 * sizeof(GLuint)));
glUniform3f(glGetUniformLocation(program, "color"), 0.0f, 0.0f, 1.0f);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, (void*)(24 * sizeof(GLuint)));
glUniform3f(glGetUniformLocation(program, "color"), 1.0f, 0.0f, 1.0f);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, (void*)(30 * sizeof(GLuint)));
}
void draw(void) {
handleInputs();
glClear(GL_COLOR_BUFFER_BIT);
glUseProgram(program);
glBindVertexArray(vao);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, cubeIndicesBufferObject);
step += 0.002f;
if (step > 1.0f) step -= 1.0f;
GLfloat stepi = step * pi * 2;
// ------------- MODEL TRANSFORMATION ---------------------
// SCALE -> ROTATE -> TRANSLATE
// GLfloat cubePosition[3] = {0.0f, -2.0f, 0.0f};
// GLfloat cubeScale[3] = {4.0f, 0.2f, 4.0f};
// GLfloat modelTransformation[16];
// identity(modelTransformation);
// scale(modelTransformation, modelTransformation, cubeScale);
// rotateY(modelTransformation, modelTransformation, stepi);
// rotateX(modelTransformation, modelTransformation, stepi + 1.0f);
// rotateZ(modelTransformation, modelTransformation, stepi + 0.5f);
// translate(modelTransformation, modelTransformation, cubePosition);
// ------------- VIEWING TRANSFORMATION -------------------
GLfloat origin[3] = {0.0f, 0.0f, 0.0f};
GLfloat up[3] = {0.0f, 1.0f, 0.0f};
GLfloat viewingTransformation[16];
GLfloat fixedCameraPosition[3] = {cos(stepi) * 4.0f, 1.5f, sin(stepi) * 4.0f};
lookAt(viewingTransformation, fixedCameraPosition, origin, up);
// -------------- PROJECTION TRANSFORMATION ----------------
GLfloat projectionTransformation[16];
GLfloat near = 0.1f;
GLfloat far = 5.0f;
perspectiveProjection(projectionTransformation, near, far);
// -------------- NORMALISATION TRANSFORMATION -------------
GLfloat normalisationTransformation[16];
GLfloat r = 0.2f;
GLfloat l = -0.2f;
GLfloat t = 0.2f;
GLfloat b = -0.2f;
normalisedDeviceCoordinates(normalisationTransformation, r, l, t, b, near, far);
// --------------- LAZY ASPECT RATIO ADJUSTMENT ------------
GLfloat aspectScale[16];
GLfloat aspectScaleVector[3] = {1.0f / aspectRatio, 1.0f, 1.0f};
scaling(aspectScale, aspectScaleVector);
GLfloat globalTransformation[16];
identity(globalTransformation);
multiply(globalTransformation, viewingTransformation, globalTransformation);
multiply(globalTransformation, projectionTransformation, globalTransformation);
multiply(globalTransformation, normalisationTransformation, globalTransformation);
multiply(globalTransformation, aspectScale, globalTransformation);
glUniformMatrix4fv(glGetUniformLocation(program, "globalTransformation"), 1, GL_FALSE, globalTransformation);
GLfloat position[3] = {0.0f, -2.0f, 0.0f};
GLfloat scaleVec[3] = {3.0f, 0.2f, 3.0f};
GLfloat rotateVec[3] = {0.0f, 0.0f, 0.0f};
for (int i=0; i < 10; i++) {
position[1] += 0.4;
rotateVec[1] += 0.2;
scaleVec[0] -= 0.3;
scaleVec[2] -= 0.3;
drawCube(position, scaleVec, rotateVec);
}
}
void framebuffer_size_callback(GLFWwindow *window, int width, int height) {
glViewport(0, 0, width, height);
aspectRatio = (float)width / height;
}
int main(void) {
GLfloat test[16] = {
1.0f, 2.0f, 3.0f, 4.0f,
5.0f, 6.0f, 7.0f, 8.0f,
9.0f, 1.0f, 2.0f, 3.0f,
4.0f, 5.0f, 6.0f, 7.0f
};
transpose(test, test);
GLfloat test2[16] = {
0.0f, 1.0f, 0.0f, 1.0f,
1.0f, 2.0f, 1.0f, 2.0f,
2.0f, 3.0f, 2.0f, 3.0f,
3.0f, 4.0f, 3.0f, 4.0f
};
transpose(test2, test2);
multiply(test, test, test2);
// mat4Print(test);
// return 0;
glfwInit();
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
window = glfwCreateWindow(700, 700, "Computergrafik 1", NULL, NULL);
if (!window) {
printf("Failed to create window\n");
glfwTerminate();
return -1;
}
glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
glfwMakeContextCurrent(window);
// register keyboard event handler
glfwSetKeyCallback(window, keyboardHandler);
glewInit();
printf("OpenGL version supported by this platform (%s):\n", glGetString(GL_VERSION));
init();
while (!glfwWindowShouldClose(window) && !exitRequested) {
draw();
glfwSwapBuffers(window);
glfwPollEvents();
}
glfwTerminate();
return 0;
}