modif normals lab3

lab3/src/lab3.js

@@ -158,6 +158,31 @@ function getStorageLocation(gl, name) {
   return storageLocation
 }
 
+function subtractArrays(array1, array2) {
+  result = []
+  for (let i = 0; i < array1.length; i++){
+    result.push(array1[i] - array2[i]);
+  }
+  return result;
+}
+
+function calcNormal(vertices, normals, indices) {
+  for (let i = 0; i < indices.length; i += 3) {
+    let A = [vertices[indices[i] * 3], vertices[indices[i] * 3 + 1], vertices[indices[i] * 3 + 2]];
+    let B = [vertices[indices[i + 1] * 3], vertices[indices[i + 1] * 3 + 1], vertices[indices[i + 1] * 3 + 2]];
+    let C = [vertices[indices[i + 2] * 3], vertices[indices[i + 2] * 3 + 1], vertices[indices[i + 2] * 3 + 2]];
+
+    let U = subtractArrays(B, A);
+    let V = subtractArrays(C, A);
+
+    for (let j = 0; j < 3; j++) {
+      normals[indices[i + j] * 3] = (U[1] * V[2] - U[2] * V[1]);
+      normals[indices[i + j] * 3 + 1] = (U[2] * V[0] - U[0] * V[2]);
+      normals[indices[i + j] * 3 + 2] = (U[0] * V[1] - U[1] * V[0]);
+    }
+  }
+}
+
 function initVertexBuffers(gl) {
   // This is the model
   let vertices = new Float32Array([
@@ -258,79 +283,81 @@ function initVertexBuffers(gl) {
 
   let normals = new Float32Array([
     //Grande base
-    0.0, -1.0, 0.0, 
-    0.0, -1.0, 0.0,
-    0.0, -1.0, 0.0,
-    0.0, -1.0, 0.0, 
+    0.0, 0.0, 0.0, 
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0, 
     
     //Petite base
-    0.0, 1.0, 0.0, 
-    0.0, 1.0, 0.0,
-    0.0, 1.0, 0.0,
-    0.0, 1.0, 0.0,
+    0.0, 0.0, 0.0, 
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
 
     //Face arrière
-    0.0, 0.0, 1.0, 
-    0.0, 0.0, 1.0,
-    0.0, 0.0, 1.0,
-    0.0, 0.0, 1.0,
-    0.0, 0.0, 1.0,
+    0.0, 0.0, 0.0, 
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
 
     //Face gauche
-    -1.0, 0.0, 0.0, 
-    -1.0, 0.0, 0.0,
-    -1.0, 0.0, 0.0,
-    -1.0, 0.0, 0.0,
-    -1.0, 0.0, 0.0,
+    0.0, 0.0, 0.0, 
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
 
     //Face droite
-    1.0, 0.0, 0.0, 
-    1.0, 0.0, 0.0,
-    1.0, 0.0, 0.0,
-    1.0, 0.0, 0.0,
-    1.0, 0.0, 0.0,
+    0.0, 0.0, 0.0, 
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
 
     //Face avant
-    0.0, 0.0, -1.0, 
-    0.0, 0.0, -1.0,
-    0.0, 0.0, -1.0,
-    0.0, 0.0, -1.0,
-    0.0, 0.0, -1.0,
+    0.0, 0.0, 0.0, 
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
 
     //Plain
-    0.0, 1.0, 0.0,
-    0.0, 1.0, 0.0,
-    0.0, 1.0, 0.0,
-    0.0, 1.0, 0.0
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0,
+    0.0, 0.0, 0.0
   ]);
 
   let indices = new Uint8Array([
-    0, 1, 2, //Grande base
-    1, 2, 3,
+    0, 2, 1, //Grande base
+    2, 3, 1,
 
     4, 5, 6, //Petite base
-    5, 6, 7,
+    5, 7, 6,
 
-    8, 9, 10, //Face arrière
-    9, 10, 11,
-    10, 11, 12,
+    8, 10, 9, //Face arrière
+    10, 11, 9,
+    10, 12, 11,
 
     13, 14, 15, //Face gauche
-    14, 15, 16,
-    15, 16, 17,
+    14, 16, 15,
+    16, 17, 15,
 
     18, 19, 20, //Face droite
-    19, 20, 21,
-    20, 21, 22,
-
+    19, 21, 20,
+    21, 22, 20,
+    
     23, 24, 25, //Face avant
-    24, 25, 26,
-    25, 26, 27,
+    24, 26, 25,
+    26, 27, 25,
 
     28, 29, 30, //Plain
-    29, 30, 31
+    29, 31, 30
   ]);
 
+  calcNormal(vertices, normals, indices);
+
   // Create a buffer object
   const vertexBuffer = gl.createBuffer();
   if (!vertexBuffer) {