feat: 3D support added

9 files changed, 131 insertions, 42 deletions

diff --git a/Makefile b/Makefile
index 56f81cc..aaf20db 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,5 @@
 CC 		:= cc
-CFLAGS 	:= -Wall -Wall -pedantic -std=c11
+CFLAGS 	:= -Wall -pedantic -pedantic-errors -std=c11
 DLIBS 	:= -lm $(shell pkg-config --libs glfw3 opengl glew)
 OBJDIR 	= objs
 SRCDIR  = src
diff --git a/TODO b/TODO
index d28e068..c6eeaeb 100644
--- a/TODO
+++ b/TODO
@@ -7,13 +7,10 @@ General
     - define a format for 3D objects
     - Render a set of vertices loaded from a file
 
-Learning
-* Make a Hello Window
-* Make a Hello Triangle
-* Make a Shader Loader Library
+- Implement Camera movement
 
 Linear
 - Implement the Inverse function of mat4
 - Implement the determinant function of mat4
-
-Shader
+* Check 3D perspective transformation
+- Implement Orhographic view transformation
diff --git a/shaders/fragment.vsh b/shaders/fragment.fsh
index 38bc00d..2d87daa 100644
--- a/shaders/fragment.vsh
+++ b/shaders/fragment.fsh
@@ -5,5 +5,5 @@ out vec4 FragColor;
 
 void main()
 {
-    FragColor = vec4(vertexColor, 1.0);
+    FragColor = vec4(vertexColor, 0.0f);
 }
diff --git a/shaders/vertex.vsh b/shaders/vertex.vsh
index 220041d..987dc3b 100644
--- a/shaders/vertex.vsh
+++ b/shaders/vertex.vsh
@@ -2,12 +2,12 @@
 
 layout (location = 0) in vec3 aPos;
 layout (location = 1) in vec3 aColor;
-uniform mat4 trans;
+uniform mat4 model, view, proj;
 
 out vec3 vertexColor;
 
 void main()
 {
-    gl_Position = trans * vec4(aPos, 1.0f);
+    gl_Position = proj * view * model * vec4(aPos, 1.0f);
     vertexColor = aColor;
 }
diff --git a/src/linear.c b/src/linear.c
index 06c2e33..4a4c958 100644
--- a/src/linear.c
+++ b/src/linear.c
@@ -1,10 +1,13 @@
 #include "linear.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
 #include <math.h>
 
 mat4
 linearLookAt(vec3 position, vec3 target, vec3 world_up)
 {
-    mat4 out = linearMat4Identity();
+    mat4 out = linearMat4Identity(1.0);
     mat4 translate;
     vec3 cam_dir, cam_right, cam_up;
     /* position - target */
@@ -33,8 +36,8 @@ linearPerspective(float FoV, float ratio, float near, float far)
 {
     mat4 out = linearMat4Fill(0.0);
     float FoV_radians = FoV * M_PI / 180;
-    float width = near * tanf(FoV_radians) * ratio;
-    float height = near * tanf(FoV_radians);
+    float width = near * tanf(FoV_radians);
+    float height = near * tanf(FoV_radians) * ratio;
 
     out.matrix[0][0] = near / width;
     out.matrix[1][1] = near / height;
@@ -47,7 +50,7 @@ linearPerspective(float FoV, float ratio, float near, float far)
 mat4
 linearTranslate(float T_x, float T_y, float T_z)
 {
-    mat4 out = linearMat4Identity();
+    mat4 out = linearMat4Identity(1.0);
     out.matrix[0][3] = T_x;
     out.matrix[1][3] = T_y;
     out.matrix[2][3] = T_z;
@@ -63,7 +66,7 @@ linearTranslatev(vec3 T)
 mat4
 linearScale(float S_x, float S_y, float S_z)
 {
-    mat4 out = linearMat4Identity();
+    mat4 out = linearMat4Identity(1.0);
     out.matrix[0][0] = S_x;
     out.matrix[1][1] = S_y;
     out.matrix[2][2] = S_z;
@@ -77,9 +80,9 @@ linearScalev(vec3 S)
 }
 
 mat4
-linearRotate(float degree, vec3 R_xyz)
+linearRotatev(float degree, vec3 R_xyz)
 {
-    mat4 out = linearMat4Identity();
+    mat4 out = linearMat4Identity(1.0);
     vec3 R_xyz_normalized = linearVec3Normalize(R_xyz);
     float radians = degree * M_PI/180.0;
     float Rx = R_xyz_normalized.vector[0];
@@ -88,7 +91,7 @@ linearRotate(float degree, vec3 R_xyz)
     float rcos = cosf(radians);
     float rsin = sinf(radians);
 
-    out.matrix[0][0] = rcos + pow(Rx, 2) * ( 1 - rcos);
+    out.matrix[0][0] = rcos + pow(Rx, 2) * (1 - rcos);
     out.matrix[0][1] = Rx * Ry * (1 - rcos) - Rz * rsin;
     out.matrix[0][2] = Rx * Rz * (1 - rcos) + Ry * rsin;
 
@@ -103,6 +106,12 @@ linearRotate(float degree, vec3 R_xyz)
 }
 
 mat4
+linearRotate(float degree, float Rx, float Ry, float Rz)
+{
+    return linearRotatev(degree, linearVec3(Rx, Ry, Rz));
+}
+
+mat4
 linearMat4Fill(float value)
 {
     int i, j;
@@ -116,13 +125,13 @@ linearMat4Fill(float value)
 }
 
 mat4
-linearMat4Identity()
+linearMat4Identity(float value)
 {
     int i, j;
     mat4 out;
     for (i = 0; i < 4; i++) {
         for (j = 0; j < 4; j++) {
-            if (i == j) out.matrix[i][j] = 1.0;
+            if (i == j) out.matrix[i][j] = value;
             else out.matrix[i][j] = 0.0;
         }
     }
@@ -158,6 +167,27 @@ linearMat4Mul(mat4 x1, mat4 x2)
 }
 
 mat4
+linearMat4Muln(int n, ...)
+{
+    mat4 out;
+
+    if (n <= 0) {
+        fprintf(stderr, "linearMat4Muln() Error: the specified number of args must be a positive integer greater than 0\n");
+    }
+
+    va_list(ap);
+    va_start(ap, n);
+    out = va_arg(ap, mat4);
+
+    int i;
+    for (i = 1; i < n; i++) {
+        out = linearMat4Mul(out, va_arg(ap, mat4));
+    }
+    va_end(ap);
+    return out;
+}
+
+mat4
 linearMat4Add(mat4 x1, mat4 x2)
 {
     int i, j;
diff --git a/src/linear.h b/src/linear.h
index 86b93d7..c5f40aa 100644
--- a/src/linear.h
+++ b/src/linear.h
@@ -13,17 +13,19 @@ typedef struct {
     float vector[3];
 } vec3;
 
-mat4 linearTranslatev(vec3 translate_vector); //TODO
-mat4 linearScalev(vec3 scale_vector); //TODO
+mat4 linearTranslatev(vec3 translate_vector);
+mat4 linearRotatev(float degree, vec3 rotation_axis);
+mat4 linearScalev(vec3 scale_vector);
 mat4 linearTranslate(float translate_x, float translate_y, float translate_z);
 mat4 linearScale(float scale_x, float scale_y, float scale_z);
-mat4 linearRotate(float degree, vec3 rotation_axis);
+mat4 linearRotate(float degree, float rotate_x, float rotate_y, float rotate_z);
 mat4 linearPerspective(float FoV, float ratio, float near, float far);
 mat4 linearLookAt(vec3 position, vec3 target, vec3 up);
 
 mat4 linearMat4Fill(float value);
-mat4 linearMat4Identity();
+mat4 linearMat4Identity(float value);
 mat4 linearMat4Mul(mat4 x1, mat4 x2);
+mat4 linearMat4Muln(int n, ...);
 mat4 linearMat4Transpose(mat4 x);
 mat4 linearMat4Inv(mat4 x); //TODO
 mat4 linearMat4Add(mat4 x1, mat4 x2); //TODO
diff --git a/src/main.c b/src/main.c
index 27181ef..7cded68 100644
--- a/src/main.c
+++ b/src/main.c
@@ -3,7 +3,9 @@
 #include <errno.h>
 #include <string.h>
 #include <signal.h>
+#include <stdarg.h>
 
+#include <math.h>
 #include <GL/glew.h>
 #include <GLFW/glfw3.h>
 
@@ -12,21 +14,42 @@
 #include "shader.h"
 
 float vertices[] = {
-    -0.5f, -0.5f, 0.0f, 1.0f, 1.0f, 0.0f,
-    0.5f, -0.5f, 0.0f, 1.0f, 1.0f, 0.0f,
-    -0.5f, 0.5f, 0.0f, 1.0, 1.0f, 0.0f,
-    0.5f, 0.5f, 0.0f, 1.0, 1.0f, 0.0f,
+    -0.5,-0.5,-0.5, 1.0, 1.0, 1.0,
+     0.5,-0.5,-0.5, 1.0, 1.0, 0.0,
+    -0.5, 0.5,-0.5, 1.0, 0.0, 1.0,
+     0.5, 0.5,-0.5, 1.0, 0.0, 0.0,
+    -0.5,-0.5, 0.5, 0.0, 1.0, 1.0,
+     0.5,-0.5, 0.5, 0.0, 1.0, 0.0,
+    -0.5, 0.5, 0.5, 0.0, 0.0, 1.0,
+     0.5, 0.5, 0.5, 0.0, 0.0, 0.0,
 };
 
 unsigned int indices[] = {
     0, 1, 2,
-    2, 3, 1
+    2, 3, 1,
+
+    4, 5, 7,
+    7, 6, 4,
+
+    1, 3, 5,
+    3, 7, 5,
+
+    6, 0, 2,
+    6, 0, 4,
+
+    2, 7, 6,
+    2, 7, 3,
+
+    0, 1, 5,
+    0, 4, 5
 };
 
 static void userError(const char *msg, const char *detail);
 static void glfw_size_callback(GLFWwindow *window, int width, int height);
 static void processInput(GLFWwindow *window);
 
+static void linearPrintMat4(mat4 x);
+
 void
 userError(const char *msg, const char *detail)
 {
@@ -34,7 +57,7 @@ userError(const char *msg, const char *detail)
     exit(1);
 }
 
-static void
+void
 glfw_size_callback(GLFWwindow *window, int width, int height)
 {
     glViewport(0, 0, width, height);
@@ -55,6 +78,19 @@ processInput(GLFWwindow *window)
         glPolygonMode(GL_FRONT_AND_BACK, GL_POINT);
 }
 
+void
+linearPrintMat4(mat4 x)
+{
+    int i, j;
+    for (i = 0; i < 4; i++) {
+        for (j = 0; j < 4; j++) {
+            printf("%f ", x.matrix[i][j]);
+        }
+        printf("\n");
+    }
+    printf("\n");
+}
+
 int main()
 {
     GLFWwindow *window;
@@ -81,6 +117,8 @@ int main()
         userError("glewInit() failed", (const char *)glewGetErrorString(glewErrno));
     }
 
+    glEnable(GL_DEPTH_TEST);
+
     unsigned int VBO, VAO, EBO;
     glGenVertexArrays(1, &VAO);
     glGenBuffers(1, &VBO);
@@ -103,25 +141,46 @@ int main()
     glBindVertexArray(0);
 
     unsigned int shaderProgram = shaderCreateProgram("shaders/vertex.vsh", 
-                                                     "shaders/fragment.vsh");
+                                                     "shaders/fragment.fsh");
 
-    unsigned int transformLoc;
-    mat4 transform;
+    unsigned int modelLoc, viewLoc, projLoc;
+    mat4 model, view, proj;
+    mat4 T, S, R;
 
+    float t;
     while (!glfwWindowShouldClose(window)) {
         processInput(window);
 
         glClearColor(0.2f, 0.2f, 0.2f, 1.0f);
-        glClear(GL_COLOR_BUFFER_BIT);
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+        t = (float)glfwGetTime();
+        T = linearTranslate(0.0, 0.0, 0.0);
+        R = linearRotate(180 * t / M_PI, 0.0, 1.0, 0.0);
+        S = linearScale(1.0, 1.0, 1.0);
 
+        model = linearMat4Muln(3, T, R, S);
+
+        T = linearTranslate(0.0, -0.0, -80);
+        R = linearRotate(60, 1, 0, 0);
+
+        view = linearMat4Muln(2, T, R);
+
+        proj = linearPerspective(35, 4 / 3.0, 0.1, 100);
         glUseProgram(shaderProgram);
         glBindVertexArray(VAO);
         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
 
-        transformLoc = glGetUniformLocation(shaderProgram, "trans");
-        transform = linearRotate(45.0, linearVec3(0, 0, 1));
-        glUniformMatrix4fv(transformLoc, 1, GL_FALSE, transform.matrix[0]);
-        glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
+        modelLoc = glGetUniformLocation(shaderProgram, "model");
+        viewLoc = glGetUniformLocation(shaderProgram, "view");
+        projLoc = glGetUniformLocation(shaderProgram, "proj");
+
+        glUniformMatrix4fv(modelLoc, 1, GL_TRUE, model.matrix[0]);
+        glDrawElements(GL_TRIANGLES, sizeof(indices) / sizeof(int), GL_UNSIGNED_INT, 0);
+        glUniformMatrix4fv(viewLoc, 1, GL_TRUE, view.matrix[0]);
+        glDrawElements(GL_TRIANGLES, sizeof(indices) / sizeof(int), GL_UNSIGNED_INT, 0);
+        glUniformMatrix4fv(projLoc, 1, GL_TRUE, proj.matrix[0]);
+        glDrawElements(GL_TRIANGLES, sizeof(indices) / sizeof(int), GL_UNSIGNED_INT, 0);
 
         glfwSwapBuffers(window);
         glfwPollEvents();
diff --git a/src/main.h b/src/main.h
index e4fc1ee..d93f941 100644
--- a/src/main.h
+++ b/src/main.h
@@ -1,4 +1,6 @@
-struct Background {
-    float R, G, B, A;
-};
+typedef struct {
+    float pos[3];
+    float color[3];
+} vertex;
 
+enum AXIS {X_AXIS, Y_AXIS, Z_AXIS};
diff --git a/src/shader.c b/src/shader.c
index e21277f..700628f 100644
--- a/src/shader.c
+++ b/src/shader.c
@@ -1,6 +1,5 @@
 #include <stdio.h>
 #include <stdlib.h>
-#include <stdarg.h>
 #include <GL/glew.h>
 #include "shader.h"