This commit is contained in:
Luca Conte 2024-04-18 22:17:22 +02:00
parent 28177633ed
commit 9608484ce1
6 changed files with 597 additions and 0 deletions

21
u05-1/Makefile Normal file
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GLEW_LIBS=$(shell pkgconf glew --libs)
GLFW_LIBS=$(shell pkgconf glfw3 --libs)
OBJ = main.o matrixMath.o
cg1.out: $(OBJ) vertexShader.c fragmentShader.c matrixMath.h
gcc -o $@ $(OBJ) -lm $(GLEW_LIBS) $(GLFW_LIBS)
%Shader.c: %Shader.glsl
xxd -i $? > $@
main.o: vertexShader.c fragmentShader.c
%.o: %.c
gcc -c $<
run: cg1.out
./cg1.out
clean:
rm vertexShader.c fragmentShader.c cg1.out *.o

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#version 330 core
in vec3 color;
void main() {
gl_FragColor = vec4(color, 1.0);
}

281
u05-1/main.c Normal file
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#include <stdio.h>
#include <GL/glew.h>
#include <GLFW/glfw3.h>
#include "vertexShader.c"
#include "fragmentShader.c"
#include "matrixMath.h"
#include <stdlib.h>
#include <math.h>
#include <string.h>
#define RESTART 345678
GLuint program;
GLuint vao;
GLuint cubeIndicesBufferObject;
GLfloat aspectRatio = 1.0f;
GLfloat step = 0.0f;
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 init(void) {
// create and compile vertex shader
GLchar *vertexText = malloc(vertexShader_glsl_len);
memcpy(vertexText, vertexShader_glsl, vertexShader_glsl_len);
const GLchar *vertexTextConst = vertexText;
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);
}
free(vertexText);
vertexText = NULL;
vertexTextConst = NULL;
// create and compile fragment shader
GLchar *fragmentText = malloc(fragmentShader_glsl_len);
memcpy(fragmentText, fragmentShader_glsl, fragmentShader_glsl_len);
const GLchar *fragmentTextConst = fragmentText;
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);
}
free(fragmentText);
fragmentText = NULL;
fragmentTextConst = NULL;
// 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);
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 draw(void) {
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 M[16];
identity(M);
// GLfloat cameraPosition[3] = {sin(step * 2 * 3.14169f), 0.3f, 0.3f};
GLfloat cameraPosition[3] = {0.6f, 0.3f, 0.3f};
GLfloat cubePosition[3] = {0.0f, 0.0f, sin(step * 2 * 3.14159)};
GLfloat up[3] = {0.0f, 1.0f, 0.0f};
lookAt(M, cameraPosition, cubePosition, up);
// GLfloat scaleFactor = sin(step * 3.14159f * 2) * 0.1f + 0.2f;
GLfloat scaleFactor = 0.5f;
GLfloat aspectScale[3] = {1.0f / aspectRatio, 1.0f, 1.0f};
GLfloat scaleBy[3] = {scaleFactor, scaleFactor, scaleFactor};
// rotateY(M, M, step * 3.14159f * 2);
// rotateX(M, M, step * 3.14159f * 2 + 1.0f);
// rotateZ(M, M, step * 3.14159f * 2 + 0.5f);
scale(M, M, aspectScale);
// translate(M, M, cubePosition);
scale(M, M, scaleBy);
glUniformMatrix4fv(glGetUniformLocation(program, "transformation"), 1, GL_FALSE, M);
glDrawElements(GL_TRIANGLES, sizeof(cubeIndices) / sizeof(GLuint), GL_UNSIGNED_INT, NULL);
}
void framebuffer_size_callback(GLFWwindow *window, int width, int height) {
glViewport(0, 0, width, height);
aspectRatio = (float)width / height;
}
int main(void) {
// GLfloat a[3];
// GLfloat b[3];
// vec3Zero(a);
// vec3Zero(b);
// a[0] = 1;
// a[1] = 2;
// a[2] = 3;
// vec3Normalise(a, a);
// printf("%f %f %f\n", a[0], a[1], a[2]);
// return 0;
glfwInit();
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
GLFWwindow *window = glfwCreateWindow(600, 600, "Computergrafik 1", NULL, NULL);
if (!window) {
printf("Failed to create window\n");
glfwTerminate();
return -1;
}
glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
glfwMakeContextCurrent(window);
glewInit();
printf("OpenGL version supported by this platform (%s):\n", glGetString(GL_VERSION));
init();
while (!glfwWindowShouldClose(window)) {
draw();
glfwSwapBuffers(window);
glfwPollEvents();
}
glfwTerminate();
return 0;
}

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u05-1/matrixMath.c Normal file
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#include <math.h>
#include <stdlib.h>
#include <stdio.h>
#include <GL/glew.h>
#include <string.h>
void vec3Zero(GLfloat* out) {
for (int i = 0; i < 3; i++) {
out[i] = 0;
}
}
void vec3Add(GLfloat* out, GLfloat* a, GLfloat* b) {
for (int i = 0; i < 3; i++) {
out[i] = a[i] + b[i];
}
}
void vec3Multiply(GLfloat* out, GLfloat* a, GLfloat x) {
for (int i = 0; i < 3; i++) {
out[i] = a[i] * x;
}
}
void vec3Subtract(GLfloat* out, GLfloat* a, GLfloat* b) {
vec3Multiply(out, b, -1);
vec3Add(out, a, out);
}
void vec3Cross(GLfloat* out, GLfloat* a, GLfloat* b) {
GLfloat result[3];
result[0] = a[1] * b[2] - a[2] * b[1];
result[1] = a[2] * b[0] - a[0] * b[2];
result[2] = a[0] * b[1] - a[1] * b[0];
memcpy(out, result, sizeof(result));
}
GLfloat vec3Length(GLfloat* a) {
return (GLfloat)sqrt(a[0]*a[0] + a[1]*a[1] + a[2]*a[2]);
}
GLfloat vec3Dot(GLfloat* a, GLfloat* b) {
return a[0] * b[0] + a[1] * b[1] + a[2] * b[2];
}
void vec3Normalise(GLfloat* out, GLfloat* a) {
vec3Multiply(out, a, 1 / vec3Length(a));
}
// CREATE 4x4 IDENTITY MATRIX
void identity(GLfloat* out) {
for (int i = 0; i < 16; i++) {
out[i] = (i % 4 == i / 4);
}
}
// CREATE 4x4 TRANSLATION MATRIX
void translation(GLfloat* out, GLfloat* v) {
identity(out);
for (int i = 0; i < 3; i++) {
out[3 * 4 + i] = v[i];
}
}
// CREATE 4x4 SCALING MATRIX
void scaling(GLfloat* out, GLfloat* v) {
identity(out);
for (int i = 0; i < 3; i++) {
out[i * 5] = v[i];
}
}
// CREATE 4x4 ROTATION MATRIX AROUND Z AXIS
/* cos a -sin a 0 0
* sin a cos a 0 0
* 0 0 1 0
* 0 0 0 1
*/
void rotationZ(GLfloat* out, GLfloat angle) {
identity(out);
out[0] = cos(angle);
out[1] = sin(angle);
out[4] = -sin(angle);
out[5] = cos(angle);
}
// CREATE 4x4 ROTATION MATRIX AROUND Y AXIS
void rotationY(GLfloat* out, GLfloat angle) {
identity(out);
out[0] = cos(angle);
out[2] = -sin(angle);
out[8] = sin(angle);
out[10] = cos(angle);
}
// CREATE 4x4 ROTATION MATRIX AROUND Y AXIS
void rotationX(GLfloat* out, GLfloat angle) {
identity(out);
out[5] = cos(angle);
out[6] = sin(angle);
out[9] = -sin(angle);
out[10] = cos(angle);
}
// MULTIPLY ANY TO MATRICES
void multiplyAny(GLfloat* A, GLfloat* B, GLfloat* out, int wA, int hA, int wB) {
int sizeOut = hA * wB;
GLfloat* result = (GLfloat*) malloc(sizeOut * sizeof(GLfloat));
for (int i = 0; i < sizeOut; i++) {
result[i] = 0;
// printf("%d: ", i);
for (int j = 0; j < wA; j++) {
// printf("%d : %f ", j * hA + i % hA, A[j * hA + i % hA]);
result[i] += A[j * hA + i % hA] * B[j + i / hA * wB];
}
// printf("\n");
}
memcpy(out, result, sizeOut * sizeof(GLfloat));
free(result);
result = NULL;
}
// MULTIPLY TWO 4x4 MATRICES
void multiply(GLfloat* A, GLfloat* B, GLfloat* out) {
multiplyAny(A, B, out, 4, 4, 4);
}
// MULTIPLY in WITH TRANSLATION MATRIX OF v
void translate(GLfloat* out, GLfloat* in, GLfloat* v) {
GLfloat translationMatrix[16];
translation(translationMatrix, v);
multiply(translationMatrix, in, out);
}
// MULTIPLY in WITH SCALING MATRIX OF v
void scale(GLfloat* out, GLfloat* in, GLfloat* v) {
GLfloat scalingMatrix[16];
scaling(scalingMatrix, v);
multiply(scalingMatrix, in, out);
}
// MULTIPLY in WITH ROTATION MATRIX OF a AROUND Z AXIS
void rotateZ(GLfloat* out, GLfloat* in, GLfloat angle) {
GLfloat rotationMatrix[16];
rotationZ(rotationMatrix, angle);
multiply(rotationMatrix, in, out);
}
// MULTIPLY in WITH ROTATION MATRIX OF a AROUND Y AXIS
void rotateY(GLfloat* out, GLfloat* in, GLfloat angle) {
GLfloat rotationMatrix[16];
rotationY(rotationMatrix, angle);
multiply(rotationMatrix, in, out);
}
// MULTIPLY in WITH ROTATION MATRIX OF a AROUND X AXIS
void rotateX(GLfloat* out, GLfloat* in, GLfloat angle) {
GLfloat rotationMatrix[16];
rotationX(rotationMatrix, angle);
multiply(rotationMatrix, in, out);
}
void transposeAny(GLfloat* out, GLfloat* in, int w, int h) {
int size = w * h;
GLfloat* result = (GLfloat*) malloc(size * sizeof(GLfloat));
for (int i = 0; i < size; i++) {
result[i] = in[(i % w) * h + i / w];
}
memcpy(out, result, size * sizeof(GLfloat));
free(result);
result = NULL;
}
void transpose(GLfloat* out, GLfloat* in) {
transposeAny(out, in, 4, 4);
}
void printAny(GLfloat* M, int w, int h) {
GLfloat* transposed = (GLfloat*) malloc(w * h * sizeof(GLfloat));
transposeAny(transposed, M, w, h);
for (int i = 0; i < h; i++) {
for (int j = 0; j < w; j++) {
printf("%.4f ", transposed[i * w + j]);
}
printf("\n");
}
free(transposed);
transposed = NULL;
}
void vec3Print(GLfloat* a) {
printAny(a, 1, 3);
}
void mat4Print(GLfloat* m) {
printAny(m, 4, 4);
}
void lookAt(GLfloat* out, GLfloat* eye, GLfloat* center, GLfloat* up) {
GLfloat n[3];
vec3Subtract(n, eye, center);
GLfloat u[3];
vec3Cross(u, up, n);
GLfloat v[3];
vec3Cross(v, n, u);
vec3Normalise(n, n);
vec3Normalise(u, u);
vec3Normalise(v, v);
GLfloat Mr[16];
identity(Mr);
memcpy(&Mr[0], u, sizeof(GLfloat) * 3);
memcpy(&Mr[4], v, sizeof(GLfloat) * 3);
memcpy(&Mr[8], n, sizeof(GLfloat) * 3);
transpose(Mr, Mr);
GLfloat t[3];
vec3Multiply(u, u, -1);
vec3Multiply(v, v, -1);
vec3Multiply(n, n, -1);
t[0] = vec3Dot(u, eye);
t[1] = vec3Dot(v, eye);
t[2] = vec3Dot(n, eye);
memcpy(&Mr[12], t, sizeof(GLfloat) * 3);
memcpy(out, Mr, sizeof(GLfloat) * 16);
}

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u05-1/matrixMath.h Normal file
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#ifndef MATRIX_MATH
#define MATRIX_MATH
#include <GL/glew.h>
void vec3Zero(GLfloat* out);
void vec3Add(GLfloat* out, GLfloat* a, GLfloat* b);
void vec3Multiply(GLfloat* out, GLfloat* a, GLfloat x);
void vec3Subtract(GLfloat* out, GLfloat* a, GLfloat* b);
void vec3Cross(GLfloat* out, GLfloat* a, GLfloat* b);
void vec3Normalise(GLfloat* out, GLfloat* a);
GLfloat vec3Length(GLfloat* a);
GLfloat vec3Dot(GLfloat* a, GLfloat* b);
void identity(GLfloat* out);
void translation(GLfloat* out, GLfloat* v);
void scaling(GLfloat* out, GLfloat* v);
void rotationZ(GLfloat* out, GLfloat angle);
void rotationY(GLfloat* out, GLfloat angle);
void rotationX(GLfloat* out, GLfloat angle);
void multiplyAny(GLfloat* A, GLfloat* B, GLfloat* out, int wA, int hA, int wB);
void multiply(GLfloat* A, GLfloat* B, GLfloat* out);
void translate(GLfloat* out, GLfloat* in, GLfloat* v);
void scale(GLfloat* out, GLfloat* in, GLfloat* v);
void rotateZ(GLfloat* out, GLfloat* in, GLfloat angle);
void rotateY(GLfloat* out, GLfloat* in, GLfloat angle);
void rotateX(GLfloat* out, GLfloat* in, GLfloat angle);
void transposeAny(GLfloat* out, GLfloat* in, int w, int h);
void transpose(GLfloat* out, GLfloat* in);
void printAny(GLfloat* M, int w, int h);
void vec3Print(GLfloat* a);
void mat4Print(GLfloat* m);
void lookAt(GLfloat* out, GLfloat* eye, GLfloat* center, GLfloat* up);
#endif

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u05-1/vertexShader.glsl Normal file
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#version 330 core
layout (location = 0) in vec3 aPosition;
uniform mat4 transformation;
out vec3 color;
void main() {
color = aPosition / 2 + vec3(0.5, 0.5, 0.5);
gl_Position = transformation * vec4(aPosition, 1.0);
}