From 50462669066b364b7d39f75bd02454b8ed64e130 Mon Sep 17 00:00:00 2001
From: Luca Conte <main@lugico.de>
Date: Sun, 20 Apr 2025 02:04:02 +0200
Subject: [PATCH] solid cube

---
 src/main.c              | 56 ++++++++++++++++++++++++-----------------
 src/shaders/vertex.glsl |  2 +-
 2 files changed, 34 insertions(+), 24 deletions(-)

diff --git a/src/main.c b/src/main.c
index cbd1081..468ade5 100644
--- a/src/main.c
+++ b/src/main.c
@@ -25,6 +25,7 @@ GLuint initialWindowWidth = 800;
 GLuint initialWindowHeight = 600;
 
 GLfloat aspect;
+mat4 projectionMatrix;
 
 int frameCount = 0;
 struct timespec last_time, current_time;
@@ -81,6 +82,11 @@ void updateStatusDisplay() {
 	}
 }
 
+void recalculateProjectionMatrix() {
+	mat4BuildPerspective(projectionMatrix, 60 * M_PI / 180, aspect, 0.1, 10);
+	DEBUG("Recalculating Projection Matrix");
+}
+
 void init(void) {
 
 	INFO("Compiling Shaders...");
@@ -153,24 +159,23 @@ void init(void) {
 	glPrimitiveRestartIndex(restart);
 
 	GLuint indices[] = {
-		0, 1,
-		0, 2,
-		0, 4,
+		0, 1, 2, 
+		1, 2, 3,
 
-		1, 3,
-		1, 5,
+		0, 4, 1,
+		5, 4, 1,
 
-		2, 3,
-		2, 6,
+		5, 1, 7,
+		3, 1, 7,
 
-		3, 7,
+		7, 5, 6,
+		4, 5, 6,
 
-		4, 5,
-		4, 6,
+		4, 0, 6,
+		2, 0, 6,
 
-		5, 7,
-
-		6, 7
+		2, 3, 6,
+		7, 3, 6
 	};
 
 	DEBUG("Creating vertext buffer");
@@ -212,8 +217,12 @@ void init(void) {
 	// glEnable(GL_CULL_FACE);
 	glFrontFace(GL_CCW);
 
+	glEnable(GL_DEPTH_TEST);
+
 	initialiseStatusDisplay();
 
+	recalculateProjectionMatrix();
+
 	INFO("--- Initialisation done ---");
 }
 
@@ -225,7 +234,7 @@ void draw(void) {
 	currentHue += 0.0005f;
 	if (currentHue > 1.0) currentHue = 0.0f;
 
-	glClear(GL_COLOR_BUFFER_BIT);
+	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 	glUseProgram(program);
 
 	mat4 transformMatrix;
@@ -234,38 +243,39 @@ void draw(void) {
 	mat4Identity(transformMatrix);
 	mat4Scale(transformMatrix, transformMatrix, scale);
 	
-	// mat4RotateZ(transformMatrix, transformMatrix, currentHue * PI * 2);
-	// mat4RotateY(transformMatrix, transformMatrix, currentHue * PI * 2);
+	mat4RotateZ(transformMatrix, transformMatrix, currentHue * PI * 2);
+	mat4RotateY(transformMatrix, transformMatrix, currentHue * PI * 2);
 
 	mat4Translate(transformMatrix, transformMatrix, position);
-	
+
 	mat4 viewMatrix;
 	mat4Identity(viewMatrix);
-	vec3 cameraPos = {0.0f, sin(currentHue * PI * 2), 0.0f};
-	vec3 cameraLookAt = {0.0f, sin(currentHue * PI * 2), -1.0f};
+	vec3 cameraPos = {0.0f, 0.0f, 0.0f};
+	vec3 cameraLookAt = {0.0f, 0.0f, -1.0f};
 	vec3 cameraUp = {0.0f, 1.0f, 0.0f};
 	mat4BuildLookAt(viewMatrix, cameraPos, cameraLookAt, cameraUp);
 
 	mat4 modelViewMatrix;
 	mat4Multiply(modelViewMatrix, viewMatrix, transformMatrix);
 
+
 	GLuint modelViewLocation = glGetUniformLocation(program, "uModelView");
 	glUniformMatrix4fv(modelViewLocation, 1, GL_FALSE, modelViewMatrix);
 
-	mat4 projectionMatrix;
-	mat4BuildPerspective(projectionMatrix, 60 * M_PI / 180, aspect, 0.1, 10);
-
 	GLuint projectionLocation = glGetUniformLocation(program, "uProjection");
 	glUniformMatrix4fv(projectionLocation, 1, GL_FALSE, projectionMatrix);
 
+
 	glBindVertexArray(vertexArrayObject);
 	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBuffer);
-	glDrawElements(GL_LINES, 24, GL_UNSIGNED_INT, 0);
+	glDrawElements(GL_TRIANGLES, 48, GL_UNSIGNED_INT, 0);
 }
 
 void framebuffer_size_callback(GLFWwindow* window, int width, int height) {
 	glViewport(0, 0, width, height);
 	aspect = (float)width / height;
+
+	recalculateProjectionMatrix();
 }
 
 int main(int argc, char const *argv[])
diff --git a/src/shaders/vertex.glsl b/src/shaders/vertex.glsl
index d718752..9b02b75 100644
--- a/src/shaders/vertex.glsl
+++ b/src/shaders/vertex.glsl
@@ -6,6 +6,6 @@ uniform mat4 uProjection;
 out vec3 vertexColor;
 
 void main() {
-	vertexColor = vec3(1.0, 0.1, 0.1);
+	vertexColor = (aPosition + vec3(1)) / 2;
 	gl_Position = uProjection * uModelView * vec4(aPosition, 1.0);
 }
\ No newline at end of file