From c26a4724f064af980e7e4b6fda2d9eb7c1147f7f Mon Sep 17 00:00:00 2001
From: Luca Conte <main@lugico.de>
Date: Sun, 23 Jun 2024 15:49:27 +0200
Subject: [PATCH] verschlimmbesserung und so

---
 src/main.c                  | 82 +++++++++++++++++++++++++++++++++----
 src/skyboxVertexShader.glsl |  6 +--
 2 files changed, 78 insertions(+), 10 deletions(-)

diff --git a/src/main.c b/src/main.c
index 11109af..50ca9e3 100644
--- a/src/main.c
+++ b/src/main.c
@@ -47,7 +47,8 @@ char* textureFiles[NUM_TEXTURES] = {
 	"../texture/earth/normal.png"
 };
 
-int numFaces = 0; 
+int numFaces = 0;
+int skyboxNumFaces = 0;
 
 bool exitRequested = false;
 
@@ -155,7 +156,7 @@ void loadSkyboxTexture() {
         data = stbi_load(faces[i], &width, &height, &nrChannels, 0);
         if (data) {
             glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i,
-                         0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, data);
+                         0, GL_RGB, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, data);
             stbi_image_free(data);
         } else {
             printf("Failed to load texture %s\n", faces[i]);
@@ -236,12 +237,78 @@ void initSkybox() {
         exit(1);
     }
 
+    ParsedObjFile skyboxObj = readObjFile(skyboxModel);
+    skyboxNumFaces = skyboxObj.length;
+    printf("skybox faces: %d\n", skyboxNumFaces);
+
+    // write faces to buffer
+    GLuint triangleVertexBufferObject;
+    glGenBuffers(1, &triangleVertexBufferObject);
+    glBindBuffer(GL_ARRAY_BUFFER, triangleVertexBufferObject);
+    glBufferData(GL_ARRAY_BUFFER, skyboxObj.length * sizeof(face), skyboxObj.faces, GL_STATIC_DRAW);
+    glBindBuffer(GL_ARRAY_BUFFER, 0);
+
+
+    // create vertex array object
+    glGenVertexArrays(1, &skyboxVAO);
+    glBindVertexArray(skyboxVAO);
+    glBindBuffer(GL_ARRAY_BUFFER, triangleVertexBufferObject);
+
+    // vertex positions
+    glVertexAttribPointer(
+        0,
+        3,
+        GL_FLOAT,
+        GL_FALSE,
+        sizeof(vertex),
+        0
+    );
+    glEnableVertexAttribArray(0);
+
+    // vertex normals
+    glVertexAttribPointer(
+        1,
+        3,
+        GL_FLOAT,
+        GL_FALSE,
+        sizeof(vertex),
+        (void*) offsetof(vertex, normal)
+    );
+    glEnableVertexAttribArray(1);
+
+    // vertex texture coordinates
+    glVertexAttribPointer(
+        2,
+        2,
+        GL_FLOAT,
+        GL_FALSE,
+        sizeof(vertex),
+        (void*) offsetof(vertex, texture)
+    );
+    glEnableVertexAttribArray(2);
+
+    // face tangents
+    glVertexAttribPointer(
+        3,
+        3,
+        GL_FLOAT,
+        GL_FALSE,
+        sizeof(vertex),
+        (void*) offsetof(vertex, tangent)
+    );
+    glEnableVertexAttribArray(3);
+
+    glBindBuffer(GL_ARRAY_BUFFER, 0);
+    glBindVertexArray(0);
+
     loadSkyboxTexture();
 }
 
 void renderSkybox(mat4* viewMatrix, mat4* projectionMatrix) {
-    glDepthFunc(GL_LEQUAL);
     glUseProgram(skyboxProgram);
+    glDepthFunc(GL_LEQUAL);
+    glDepthMask(GL_FALSE);
+    glDisable(GL_CULL_FACE);
 
     mat4 view = *viewMatrix;
     view.m30 = 0.0f;
@@ -251,9 +318,11 @@ void renderSkybox(mat4* viewMatrix, mat4* projectionMatrix) {
     glUniformMatrix4fv(glGetUniformLocation(skyboxProgram, "projection"), 1, GL_FALSE, (GLfloat*)projectionMatrix);
 
     glBindVertexArray(skyboxVAO);
-    glActiveTexture(GL_TEXTURE0);
+
+    glUniform1i(glGetUniformLocation(skyboxProgram, "skybox"), 10);
+    glActiveTexture(GL_TEXTURE10);
     glBindTexture(GL_TEXTURE_CUBE_MAP, skyboxTexture);
-    glDrawArrays(GL_TRIANGLES, 0, 36);
+    glDrawArrays(GL_TRIANGLES, 0, skyboxNumFaces * 3);
     glBindVertexArray(0);
 
     glDepthFunc(GL_LESS);
@@ -568,7 +637,7 @@ void draw(void) {
 	glDrawArrays(GL_TRIANGLES, 0, numFaces * 3);
 
     // draw skybox
-    renderSkybox(&viewingTransformation, &projectionTransformation);
+    renderSkybox(&viewingTransformation, &projection);
 }
 
 // change viewport size and adjust aspect ratio when changing window size
@@ -615,7 +684,6 @@ int main(int argc, char **argv) {
 	printf("OpenGL version supported by this platform (%s):\n", glGetString(GL_VERSION));
 
 	init();
-    initSkybox();
 
 	// exit when window should close or exit is requested (ESC)
 	while (!glfwWindowShouldClose(window) && !exitRequested) {
diff --git a/src/skyboxVertexShader.glsl b/src/skyboxVertexShader.glsl
index afd9479..fdf8f12 100644
--- a/src/skyboxVertexShader.glsl
+++ b/src/skyboxVertexShader.glsl
@@ -1,14 +1,14 @@
 #version 330 core
 layout (location = 0) in vec3 aPos;
+layout (location = 2) in vec3 texPos;
 
 out vec3 TexCoords;
 
 uniform mat4 projection;
 uniform mat4 view;
-uniform mat4 model;
 
 void main(){
-    TexCoords = aPos;
-    vec4 pos = projection * view * model * vec4(aPos, 1.0);
+    TexCoords = texPos;
+    vec4 pos = projection * view * vec4(aPos, 1.0);
     gl_Position = pos.xyww;
 }
\ No newline at end of file