Implement .obj loader

CMakeLists.txt

@@ -1,7 +1,7 @@
 # CMake entry point
 cmake_minimum_required (VERSION 3.0)
 project(OpenGL_Analog_Clock C)
-cmake_policy(SET CMP0072 OLD)
+cmake_policy(SET CMP0072 NEW)
 
 find_package(OpenGL REQUIRED)
 find_package(GLEW REQUIRED)
@@ -28,13 +28,16 @@ add_definitions(
 	-D_CRT_SECURE_NO_WARNINGS
 )
 
-add_executable(clock
+add_executable(
+    clock
     src/main.c
     src/clock.c
     src/shader.c
     src/matrix.c
+    src/model.c
 )
 
-target_link_libraries(clock
+target_link_libraries(
+    clock
     ${ALL_LIBS}
 )

Include/clock.h

@@ -15,8 +15,9 @@
 #include <GLFW/glfw3.h>
 
 // Include project headers
-#include <shader.h>
+#include <model.h>
 #include <matrix.h>
+#include <shader.h>
 
 // Define macros
 #define xfree(p) if (p) free((void *)p)
@@ -24,5 +25,7 @@
 // Declare functions
 
 int clock_init(GLFWwindow **);
+int clock_run(GLFWwindow *);
 
 #endif
+

Include/matrix.h

@@ -1,9 +1,12 @@
 #ifndef MATRIX_H
 #define MATRIX_H
 
-GLdouble *matrix_new(void);
+GLfloat *matrix_new(void);
 
-int matrix_transform(GLdouble *, int,
-                     GLdouble **, int);
+GLfloat *matrix_multip(GLfloat *, GLfloat *);
+
+GLfloat *matrix_transform(GLfloat *, int,
+                           GLfloat *);
 
 #endif
+

Include/model.h

@@ -0,0 +1,12 @@
+#ifndef MODEL_LOADER_H
+#define MODEL_LOADER_H
+
+typedef struct _model {
+    GLfloat *buffer;
+    size_t bufsize;
+} Model;
+
+Model * model_load(const char *path);
+
+#endif
+

Include/shader.h

@@ -4,3 +4,4 @@
 int LoadShaders(GLuint *, const char *, const char *);
 
 #endif
+

shaders/SimpleFragmentShader.fragmentshader

@@ -1,12 +1,8 @@
 #version 330 core
 
-// Ouput data
 out vec3 color;
 
-void main()
-{
-
-	// Output color = red 
-	color = vec3(1,0,0);
+void main() { 
+    color = vec3(1, 0, 0);
 
 }

src/clock.c

@@ -1,6 +1,7 @@
 #include <clock.h>
 
-int clock_init(GLFWwindow **window) {
+int
+clock_init(GLFWwindow **window) {
 	// Initialise GLFW
 	if(!glfwInit()) {
 		fprintf(stderr, "Failed to initialize GLFW\n");
@@ -40,3 +41,141 @@ int clock_init(GLFWwindow **window) {
     return 0;
 }
 
+int
+clock_run(GLFWwindow *window) {
+	GLuint VertexArrayID;
+	GLuint programID;
+
+
+	glGenVertexArrays(1, &VertexArrayID);
+	glBindVertexArray(VertexArrayID);
+
+	// Create and compile our GLSL program from the shaders
+    if (LoadShaders(&programID,
+                    "../shaders/SimpleVertexShader.vertexshader",
+                    "../shaders/SimpleFragmentShader.fragmentshader")) {
+        fprintf(stderr, "Could not load shaders.\n");
+        return -1;
+    }
+
+	static GLfloat g_vertex_buffer_data[] = { 
+		-0.3f, -0.3f, 0.0f, 1.0f,
+		 0.3f, -0.3f, 0.0f, 1.0f,
+		 0.0f,  0.3f, 0.0f, 1.0f
+	};
+    Model *model;
+    model = model_load("../cube.obj");
+
+	GLuint vertexbuffer;
+	glGenBuffers(1, &vertexbuffer);
+	glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
+	glBufferData(GL_ARRAY_BUFFER, model->bufsize*4*sizeof(GLfloat), model->buffer, GL_STATIC_DRAW);
+
+    double xpos, ypos;
+    glfwGetCursorPos(window, &xpos, &ypos);
+
+    GLfloat **matrices = malloc(2 * sizeof(GLfloat *));
+
+    GLfloat *temp = matrix_new();
+
+    //temp[0] = cos(M_PI*2/60);
+    //temp[1] = -sin(M_PI*2/60);
+    //temp[4] = sin(M_PI*2/60);
+    //temp[5] = cos(M_PI*2/60);
+
+    matrices[0] = temp;
+    temp = matrix_new();
+
+    temp[0] = cos(M_PI*2/60/4);
+    temp[8] = -sin(M_PI*2/60/4);
+    temp[2] = sin(M_PI*2/60/4);
+    temp[10] = cos(M_PI*2/60/4);
+
+    matrices[1] = temp;
+
+    GLfloat *mat = matrix_new();
+
+    for (int i = 1; i >= 0; i--) {
+        temp = matrix_multip(matrices[i], mat);
+        free(mat);
+        mat = temp;
+    }
+
+    GLfloat *projection = matrix_new();
+    GLfloat *buffer;
+    projection[14] = -1.0f;
+    buffer = matrix_new();
+    buffer[0] = (GLfloat)9/16;
+    temp = matrix_multip(projection, buffer);
+    free(projection);
+    projection = buffer;
+    temp = malloc(model->bufsize * 4 * sizeof(GLfloat));
+    buffer = malloc(model->bufsize * 4 * sizeof(GLfloat));
+    memcpy(temp, model->buffer, model->bufsize * 4 * sizeof(GLfloat));
+
+	do {
+		// Clear the screen. It's not mentioned before Tutorial 02,
+        // but it can cause flickering, so it's there nonetheless.
+		glClear(GL_COLOR_BUFFER_BIT);
+
+		// Use our shader
+		glUseProgram(programID);
+        //glfwGetCursorPos(window, &xpos, &ypos);
+        //g_vertex_buffer_data[0] = (float)xpos / 1280 * 2 - 1 - 0.15;
+        //g_vertex_buffer_data[1] = 2 - (float)ypos / 720 * 2 - 1 - 0.15;
+
+        //g_vertex_buffer_data[3] = (float)xpos / 1280 * 2 - 1 + 0.15;
+        //g_vertex_buffer_data[4] = 2 - (float)ypos / 720 * 2 - 1 - 0.15;
+
+        //g_vertex_buffer_data[6] = (float)xpos / 1280 * 2 - 1;
+        //g_vertex_buffer_data[7] = 2 - (float)ypos / 720 * 2 - 1 + 0.15;
+        buffer = matrix_transform(temp, model->bufsize, mat);
+        free(temp);
+        temp = buffer;
+        buffer = matrix_transform(buffer, model->bufsize, projection);
+        memcpy(model->buffer, buffer, model->bufsize * 4 * sizeof(GLfloat));
+        free(buffer);
+
+
+	    GLuint vertexbuffer;
+	    glGenBuffers(1, &vertexbuffer);
+	    glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
+	    glBufferData(GL_ARRAY_BUFFER, model->bufsize * 4 * sizeof(GLfloat), model->buffer, GL_STATIC_DRAW);
+
+		// 1rst attribute buffer : vertices
+		glEnableVertexAttribArray(0);
+		glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
+		glVertexAttribPointer(
+			0,                  // attribute 0. No particular reason for 0, but must match the layout in the shader.
+			4,                  // size
+			GL_FLOAT,           // type
+			GL_FALSE,           // normalized?
+			0,                  // stride
+			NULL                // array buffer offset
+		);
+
+		// Draw the triangle !
+		glDrawArrays(GL_TRIANGLES, 0, model->bufsize); // 3 indices starting at 0 -> 1 triangle
+
+		glDisableVertexAttribArray(0);
+		
+		// Swap buffers
+		glfwSwapBuffers(window);
+		glfwPollEvents();
+
+        // Check if the ESC key was pressed or the window was closed
+        usleep(1000000/60);
+	} while(glfwGetKey(window, GLFW_KEY_ESCAPE) != GLFW_PRESS &&
+		   glfwWindowShouldClose(window) == 0);
+
+	// Close OpenGL window and terminate GLFW
+    for (int i = 0; i < 2; i++) {
+        free(matrices[i]);
+    }
+    free(matrices);
+	glfwTerminate();
+
+    return 0;
+
+}
+

src/main.c

@@ -1,106 +1,14 @@
 // Include APIs
 #include "clock.h"
 
-int main(int argc, char *argv[]) {
+int
+main(int argc, char *argv[]) {
 
     GLFWwindow *window;
-	GLuint VertexArrayID;
-	GLuint programID;
-
     if (clock_init(&window)) {
         return -1;
     }
 
-	glGenVertexArrays(1, &VertexArrayID);
-	glBindVertexArray(VertexArrayID);
-
-	// Create and compile our GLSL program from the shaders
-    if (LoadShaders(&programID,
-                    "../shaders/SimpleVertexShader.vertexshader",
-                    "../shaders/SimpleFragmentShader.fragmentshader")) {
-        fprintf(stderr, "Could not load shaders.\n");
-        return -1;
-    }
-
-	static GLdouble g_vertex_buffer_data[] = { 
-		-0.3f, -0.3f, 0.3f,
-		 0.3f, -0.3f, -0.3f,
-		 0.0f,  0.3f, -0.0f
-	};
-
-	GLuint vertexbuffer;
-	glGenBuffers(1, &vertexbuffer);
-	glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
-	glBufferData(GL_ARRAY_BUFFER, sizeof(g_vertex_buffer_data), g_vertex_buffer_data, GL_STATIC_DRAW);
-
-    double xpos, ypos;
-    glfwGetCursorPos(window, &xpos, &ypos);
-
-    GLdouble **matrices = calloc(1, sizeof(GLdouble *));
-
-    GLdouble *rot_mat = matrix_new();
-
-    rot_mat[0] = cos(M_PI*2/60);
-    rot_mat[1] = -sin(M_PI*2/60);
-    rot_mat[4] = sin(M_PI*2/60);
-    rot_mat[5] = cos(M_PI*2/60);
-
-    *matrices = rot_mat;
-
-
-	do {
-		// Clear the screen. It's not mentioned before Tutorial 02,
-        // but it can cause flickering, so it's there nonetheless.
-		glClear(GL_COLOR_BUFFER_BIT);
-
-		// Use our shader
-		glUseProgram(programID);
-        //glfwGetCursorPos(window, &xpos, &ypos);
-        //g_vertex_buffer_data[0] = (float)xpos / 1280 * 2 - 1 - 0.15;
-        //g_vertex_buffer_data[1] = 2 - (float)ypos / 720 * 2 - 1 - 0.15;
-
-        //g_vertex_buffer_data[3] = (float)xpos / 1280 * 2 - 1 + 0.15;
-        //g_vertex_buffer_data[4] = 2 - (float)ypos / 720 * 2 - 1 - 0.15;
-
-        //g_vertex_buffer_data[6] = (float)xpos / 1280 * 2 - 1;
-        //g_vertex_buffer_data[7] = 2 - (float)ypos / 720 * 2 - 1 + 0.15;
-        matrix_transform(g_vertex_buffer_data, 3,
-                         matrices, 1);
-
-	    GLuint vertexbuffer;
-	    glGenBuffers(1, &vertexbuffer);
-	    glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
-	    glBufferData(GL_ARRAY_BUFFER, sizeof(g_vertex_buffer_data), g_vertex_buffer_data, GL_STATIC_DRAW);
-
-		// 1rst attribute buffer : vertices
-		glEnableVertexAttribArray(0);
-		glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
-		glVertexAttribPointer(
-			0,                  // attribute 0. No particular reason for 0, but must match the layout in the shader.
-			3,                  // size
-			GL_DOUBLE,           // type
-			GL_FALSE,           // normalized?
-			0,                  // stride
-			NULL                // array buffer offset
-		);
-
-		// Draw the triangle !
-		glDrawArrays(GL_TRIANGLES, 0, 3); // 3 indices starting at 0 -> 1 triangle
-
-		glDisableVertexAttribArray(0);
-		
-		// Swap buffers
-		glfwSwapBuffers(window);
-		glfwPollEvents();
-
-        // Check if the ESC key was pressed or the window was closed
-        usleep(1000000/60);
-	} while(glfwGetKey(window, GLFW_KEY_ESCAPE) != GLFW_PRESS &&
-		   glfwWindowShouldClose(window) == 0);
-
-	// Close OpenGL window and terminate GLFW
-	glfwTerminate();
-
-	return 0;
+	return clock_run(window);
 }
 

src/matrix.c

@@ -1,9 +1,23 @@
 #include "clock.h"
 
-static GLdouble *
-matrix_multip(GLdouble *mat1, GLdouble *mat2) {
-    GLdouble *result;
-    GLdouble dot_prod;
+
+GLfloat *
+matrix_new() {
+    GLfloat *mat;
+
+    mat = calloc(16, sizeof(GLfloat));
+    
+    for (int i = 0; i < 4; i++) {
+        mat[i*4+i] = 1;
+    }
+
+    return mat;
+}
+
+GLfloat *
+matrix_multip(GLfloat *mat1, GLfloat *mat2) {
+    GLfloat *result;
+    GLfloat dot_prod;
 
     result = matrix_new();
 
@@ -21,50 +35,32 @@ matrix_multip(GLdouble *mat1, GLdouble *mat2) {
     return result;
 }
 
-GLdouble *
-matrix_new() {
-    GLdouble *mat;
 
-    mat = calloc(16, sizeof(GLdouble));
+GLfloat *
+matrix_transform(GLfloat *vects, int vectcount,
+                 GLfloat *mat) {
+    GLfloat dot_prod;
+    GLfloat *helper = NULL;
+    GLfloat *result;
 
-    for (int i = 0; i < 4; i++) {
-        mat[i*4+i] = 1;
-    }
+    result = calloc(vectcount*4, sizeof(GLfloat));
 
-    return mat;
-}
-
-
-int
-matrix_transform(GLdouble *vects, int vectcount,
-                 GLdouble **mats, int matcount) {
-    GLdouble *mat;
-    GLdouble dot_prod;
-    GLdouble *helper = NULL;
-    GLdouble *result;
-
-    mat = matrix_new();
-    result = calloc(vectcount*3, sizeof(GLdouble));
-
-    for (int i = matcount-1; i >= 0; i--) {
-        xfree(helper);
-        helper = matrix_multip(mats[i], mat);
-        free(mat);
-        mat = helper;
-    }
 
     for (int k = 0; k < vectcount; k++) {
-        for (int j = 0; j < 3; j++) {
+        for (int j = 0; j < 4; j++) {
             dot_prod = 0;
-            for (int i = 0; i < 3; i++) {
-                dot_prod += vects[k*3+i] * mat[i+j*4];
+            for (int i = 0; i < 4; i++) {
+                dot_prod += vects[k*4+i] * mat[i+j*4];
             }
-            result[j+k*3] = dot_prod;
+            result[j+k*4] = dot_prod;
+        }
+        if (result[k*4+3] != 0.0f) {
+            GLfloat div = result[k*4+3];
+            for (int i = 0; i < 4; i++) {
+                result[k*4+i] /= div;
             }
         }
-    memcpy(vects, result, vectcount * 3 * sizeof(GLdouble));
-    free(result);
-
-    return 0;
+    }
+    return result;
 }
 

src/model.c

@@ -0,0 +1,70 @@
+#include <clock.h>
+
+Model *
+model_new(size_t size) {
+    Model *model = calloc(1, sizeof(Model));
+    model->buffer = calloc((size ? size : 1) *4 , sizeof(GLfloat));
+    model->bufsize = size;
+}
+
+void
+model_free(Model *self) {
+    free(self->buffer);
+    free(self);
+}
+
+Model *
+model_load(const char *path) {
+    Model *model;
+    GLfloat *vertices;
+    int *faces;
+    size_t vertcount, facecount;
+    char type, check, *line;
+    FILE *f;
+
+    f = fopen(path, "r");
+    line = malloc(255);
+    vertices = malloc(3 * sizeof(GLfloat));
+    faces = malloc(3 * sizeof(int));
+    type = 0;
+    vertcount = 0;
+    facecount = 0;
+
+    do {
+        check = fscanf(f, "%c", &type);
+        if (check == EOF) {
+            break;
+        }
+        else if (type == 'v') {
+            vertices = realloc(vertices, (vertcount+1)*3*sizeof(GLfloat));
+            check = fscanf(f, "%f %f %f\n", &(vertices[vertcount*3]),
+                                    &(vertices[vertcount*3+1]),
+                                    &(vertices[vertcount*3+2]));
+            vertcount++;
+        }
+        else if (type == 'f') {
+            faces = realloc(faces, (facecount+1)*3*sizeof(GLfloat));
+            check = fscanf(f, "%d %d %d\n", &(faces[facecount*3]),
+                                    &(faces[facecount*3+1]),
+                                    &(faces[facecount*3+2]));
+            facecount++;
+        }
+        else {
+            check = fscanf(f, "%*[^\n]\n", NULL);
+            continue;
+        }
+    } while(check != EOF);
+
+    model = model_new(facecount*3);
+    for (int i = 0; i < facecount; i++) {
+        for (int j = 0; j < 3; j++) {
+            for (int k = 0; k < 3; k++) {
+                model->buffer[i*12+j*4+k] = vertices[(faces[i*3+j]-1)*3+k];
+            }
+            model->buffer[i*12+j*4+3] = 1;
+        }
+    }
+
+    return model;
+}
+

src/shader.c

@@ -116,4 +116,3 @@ end:
     return retval;
 }
 
-