Feat: added compile error output for shaders and implementet first ray

march

fsq.vs

@@ -3,11 +3,11 @@ R"###(
 layout (location = 0) in vec2 aPos;
 layout (location = 1) in vec2 aTexCoords;
 
-out vec2 TexCoords;
+out vec2 texCoords;
 
 void main()
 {
-    TexCoords = aTexCoords;
+    texCoords = aTexCoords;
     gl_Position = vec4(aPos.x, aPos.y, 0.0, 1.0); 
 }  
 )###";  

main.cpp

@@ -14,7 +14,7 @@ const char *fragmentShaderSource =
 
 /*void framebuffer_size_callback(GLFWwindow* window, int width, int height)
 {
-    glViewport(0, 0, width, height);
+    glViewport(0, 0, wdth, height);
 }*/
 
 void processInput(GLFWwindow *window)
@@ -37,6 +37,23 @@ unsigned int compFragmentShader() {
     fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
     glShaderSource(fragmentShader, 1, &fragmentShaderSource, NULL);
     glCompileShader(fragmentShader);
+
+    GLint isCompiled = 0;
+    glGetShaderiv(fragmentShader, GL_COMPILE_STATUS, &isCompiled);
+    if(isCompiled == GL_FALSE)
+    {
+        GLint maxLength = 0;
+        glGetShaderiv(fragmentShader, GL_INFO_LOG_LENGTH, &maxLength);
+
+        // The maxLength includes the NULL character
+        //std::vector<GLchar> errorLog(maxLength);
+        char * errorLog = new char[maxLength]();
+        glGetShaderInfoLog(fragmentShader, maxLength, &maxLength, errorLog);
+
+        printf("\nFrag Log: %s\n",errorLog);
+
+    }
+
     return fragmentShader;
 }
 

sdf.fs

@@ -1,9 +1,36 @@
 R"###(  
 #version 330 core
+
 out vec4 FragColor;
+in vec2 texCoords;
+
+vec3 center = vec3(0.0f,0.0f,20.0f);
+float radius = 5.0f;
+
+float sphereMin(vec3 pos){
+    return length(pos - center) - radius;
+}
 
 void main()
 {
-    FragColor = vec4(1.0f, 0.5f, 0.2f, 1.0f);
+    vec3 ray = vec3(texCoords.x, texCoords.y,2.0f);
+    ray = (ray - 0.5f) * 2;
+    vec3 pos = ray;
+    float min = sphereMin(ray);
+
+    while( (min < 100.0f) && (min > 0.1f) ) {
+        ray = normalize(ray);
+        ray = ray * min;
+        pos = pos + ray;
+        min = sphereMin(pos);
+    }
+    
+    
+    if(min <= 0.2f){
+        FragColor = vec4(texCoords.x, texCoords.y, 0.2f, 1.0f);
+    } else {
+        FragColor = vec4(0.0f,0.0f,0.0f,1.0f);
+    }
+
 } 
 )###";