simplify complexity

examples/example_barycentric.cpp

@@ -98,21 +98,21 @@ void drawText(const std::string& text, float x, float y, float scale, const Vect
     }
 }
 
-int main() {
+GLFWwindow* initWindow(int width, int height, const char* title) {
     if (!glfwInit()) {
         std::cerr << "Failed to initialize GLFW\n";
-        return -1;
+        return nullptr;
     }
     
     glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
     glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
     glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
 
-    GLFWwindow* window = glfwCreateWindow(800, 800, "Barycentric Coordinates", NULL, NULL);
+    GLFWwindow* window = glfwCreateWindow(width, height, title, NULL, NULL);
     if (!window) { 
         std::cerr << "Failed to create GLFW window\n";
         glfwTerminate(); 
-        return -1; 
+        return nullptr; 
     }
     glfwMakeContextCurrent(window);
 
@@ -135,25 +135,23 @@ int main() {
         } else {
             std::cerr << "Failed to initialize GLEW: " << glewGetErrorString(glewErr) << "\n";
             glfwTerminate();
-            return -1;
+            return nullptr;
         }
     }
+    return window;
+}
 
+GLuint createShaderProgram() {
     GLuint vs = compileShader(GL_VERTEX_SHADER, vertexShaderSource);
     GLuint fs = compileShader(GL_FRAGMENT_SHADER, fragmentShaderSource);
     GLuint shaderProgram = glCreateProgram();
     glAttachShader(shaderProgram, vs);
     glAttachShader(shaderProgram, fs);
     glLinkProgram(shaderProgram);
+    return shaderProgram;
+}
 
-    // Triangle vertices as shown in the picture (Red, Green, Blue)
+void generatePointCloud(std::vector<float>& pointCloud, const Vector3<float>& A, const Vector3<float>& B, const Vector3<float>& C) {
-    // Scaled down slightly to leave room for text
-    Vector3<float> A(0.0f, 0.6f, 0.0f);   // Red dot (top)
-    Vector3<float> B(-0.6f, -0.6f, 0.0f); // Green dot (bottom left)
-    Vector3<float> C(0.6f, -0.6f, 0.0f);  // Blue dot (bottom right)
-
-    std::vector<float> pointCloud;
-    
     // Iterating over barycentric coordinates (u, v, w) from 0.0 to 1.0
     for (float u = 0.0f; u <= 1.0f; u += 0.015f) {
         for (float v = 0.0f; v <= 1.0f - u; v += 0.015f) {
@@ -167,8 +165,9 @@ int main() {
             }
         }
     }
+}
 
-    GLuint VAO_cloud, VBO_cloud;
+void setupBuffers(GLuint& VAO_cloud, GLuint& VBO_cloud, const std::vector<float>& pointCloud, GLuint& VAO_dyn, GLuint& VBO_dyn) {
     glGenVertexArrays(1, &VAO_cloud);
     glGenBuffers(1, &VBO_cloud);
     glBindVertexArray(VAO_cloud);
@@ -183,7 +182,6 @@ int main() {
     glVertexAttribPointer(3, 1, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(7 * sizeof(float)));
     glEnableVertexAttribArray(3);
 
-    GLuint VAO_dyn, VBO_dyn;
     glGenVertexArrays(1, &VAO_dyn);
     glGenBuffers(1, &VBO_dyn);
     glBindVertexArray(VAO_dyn);
@@ -197,6 +195,66 @@ int main() {
     glEnableVertexAttribArray(2);
     glVertexAttribPointer(3, 1, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(7 * sizeof(float)));
     glEnableVertexAttribArray(3);
+}
+
+void updateDynamicData(std::vector<float>& dynData, float u, float v, float w, const Vector3<float>& P, const Vector3<float>& A, const Vector3<float>& B, const Vector3<float>& C) {
+    float sizeA = 10.0f + u * 30.0f;
+    float sizeB = 10.0f + v * 30.0f;
+    float sizeC = 10.0f + w * 30.0f;
+    float sizeP = 12.0f;
+
+    dynData = {
+        // Lines from P to A, B, C
+        P.x, P.y, P.z, u, v, w, 1.0f, 1.0f,
+        A.x, A.y, A.z, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f,
+        
+        P.x, P.y, P.z, u, v, w, 1.0f, 1.0f,
+        B.x, B.y, B.z, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f,
+        
+        P.x, P.y, P.z, u, v, w, 1.0f, 1.0f,
+        C.x, C.y, C.z, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f,
+
+        // The animated dot itself (White)
+        P.x, P.y, P.z, 1.0f, 1.0f, 1.0f, sizeP, 0.0f,
+
+        // The 3 corner dots
+        A.x, A.y, A.z, 1.0f, 0.0f, 0.0f, sizeA, 0.0f,
+        B.x, B.y, B.z, 0.0f, 1.0f, 0.0f, sizeB, 0.0f,
+        C.x, C.y, C.z, 0.0f, 0.0f, 1.0f, sizeC, 0.0f
+    };
+
+    char bufA[16], bufB[16], bufC[16];
+    snprintf(bufA, sizeof(bufA), "%.2f", u);
+    snprintf(bufB, sizeof(bufB), "%.2f", v);
+    snprintf(bufC, sizeof(bufC), "%.2f", w);
+
+    // Keep text at a fixed distance from the dots
+    float distA = 0.13f;
+    float distB = 0.13f;
+    float distC = 0.13f;
+
+    drawText(bufA, A.x - 0.05f, A.y + distA, 0.1f, Vector3<float>(1,0,0), dynData);
+    drawText(bufB, B.x - 0.15f - distB, B.y - 0.05f - distB, 0.1f, Vector3<float>(0,1,0), dynData);
+    drawText(bufC, C.x + 0.05f + distC, C.y - 0.05f - distC, 0.1f, Vector3<float>(0,0,1), dynData);
+}
+
+int main() {
+    GLFWwindow* window = initWindow(800, 800, "Barycentric Coordinates");
+    if (!window) return -1;
+
+    GLuint shaderProgram = createShaderProgram();
+
+    // Triangle vertices as shown in the picture (Red, Green, Blue)
+    // Scaled down slightly to leave room for text
+    Vector3<float> A(0.0f, 0.6f, 0.0f);   // Red dot (top)
+    Vector3<float> B(-0.6f, -0.6f, 0.0f); // Green dot (bottom left)
+    Vector3<float> C(0.6f, -0.6f, 0.0f);  // Blue dot (bottom right)
+
+    std::vector<float> pointCloud;
+    generatePointCloud(pointCloud, A, B, C);
+
+    GLuint VAO_cloud, VBO_cloud, VAO_dyn, VBO_dyn;
+    setupBuffers(VAO_cloud, VBO_cloud, pointCloud, VAO_dyn, VBO_dyn);
 
     glEnable(GL_PROGRAM_POINT_SIZE);
     glEnable(GL_BLEND);
@@ -237,44 +295,8 @@ int main() {
 
         Vector3<float> P = A * u + B * v + C * w;
 
-        float sizeA = 10.0f + u * 30.0f;
+        std::vector<float> dynData;
-        float sizeB = 10.0f + v * 30.0f;
+        updateDynamicData(dynData, u, v, w, P, A, B, C);
-        float sizeC = 10.0f + w * 30.0f;
-        float sizeP = 12.0f;
-
-        std::vector<float> dynData = {
-            // Lines from P to A, B, C
-            P.x, P.y, P.z, u, v, w, 1.0f, 1.0f,
-            A.x, A.y, A.z, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f,
-            
-            P.x, P.y, P.z, u, v, w, 1.0f, 1.0f,
-            B.x, B.y, B.z, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f,
-            
-            P.x, P.y, P.z, u, v, w, 1.0f, 1.0f,
-            C.x, C.y, C.z, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f,
-
-            // The animated dot itself (White)
-            P.x, P.y, P.z, 1.0f, 1.0f, 1.0f, sizeP, 0.0f,
-
-            // The 3 corner dots
-            A.x, A.y, A.z, 1.0f, 0.0f, 0.0f, sizeA, 0.0f,
-            B.x, B.y, B.z, 0.0f, 1.0f, 0.0f, sizeB, 0.0f,
-            C.x, C.y, C.z, 0.0f, 0.0f, 1.0f, sizeC, 0.0f
-        };
-
-        char bufA[16], bufB[16], bufC[16];
-        snprintf(bufA, sizeof(bufA), "%.2f", u);
-        snprintf(bufB, sizeof(bufB), "%.2f", v);
-        snprintf(bufC, sizeof(bufC), "%.2f", w);
-
-        // Keep text at a fixed distance from the dots
-        float distA = 0.13f;
-        float distB = 0.13f;
-        float distC = 0.13f;
-
-        drawText(bufA, A.x - 0.05f, A.y + distA, 0.1f, Vector3<float>(1,0,0), dynData);
-        drawText(bufB, B.x - 0.15f - distB, B.y - 0.05f - distB, 0.1f, Vector3<float>(0,1,0), dynData);
-        drawText(bufC, C.x + 0.05f + distC, C.y - 0.05f - distC, 0.1f, Vector3<float>(0,0,1), dynData);
 
         glBindVertexArray(VAO_dyn);
         glBindBuffer(GL_ARRAY_BUFFER, VBO_dyn);