Implémentation de la conservation de l'aspect ratio quand on modifie la taille de la fenêtre

src/engine/Engine.java

@@ -27,6 +27,7 @@ public class Engine {
 
     private final int width;
     private final int height;
+    private float aspectRatio;
 
     /**
      * Create the engine and initial attributes use .init() to start the engine
@@ -36,6 +37,7 @@ public class Engine {
         this.objectsGl = new ArrayList<>();
         this.width = width;
         this.height = height;
+        this.aspectRatio = aspectRatio;
         ObjectGl.projection = Matrix4f.orthographic(-1000, 1000, -1000 * aspectRatio, 1000 * aspectRatio, 0.1f, 100.0f);
         ObjectGl.view = Matrix4f.translate(new Vector3f(0.0f, 0.0f, 1.0f));
     }
@@ -83,6 +85,7 @@ public class Engine {
 
         glEnable(GL_DEPTH_TEST); // Z-Buffer plus z est grand plus l'objet est proche de la camera limite à 100.0f au dela l'objet disparait
 
+        glScissor(0,0,this.width,this.height); // La zone de dessin du background
         glEnable(GL_BLEND); // Transparence
         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
@@ -102,6 +105,7 @@ public class Engine {
      */
     public void render() {
 
+        glEnable(GL_SCISSOR_TEST);
         glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
@@ -155,7 +159,20 @@ public class Engine {
     private static final GLFWFramebufferSizeCallback resizeWindow = new GLFWFramebufferSizeCallback() {
         @Override
         public void invoke(long window, int width, int height) {
-            glViewport(0, 0, width, height);
+            int heightViewport, widthViewport, x, y;
+            if (width >= height){
+                heightViewport = height;
+                widthViewport = (int) (height * 4.0f/3.0f);
+                y = 0;
+                x = (width - widthViewport)/2;
+            } else {
+                widthViewport = width;
+                heightViewport = (int) (width * 3.0f/4.0f);
+                y = (height - heightViewport)/2;
+                x = 0;
+            }
+            glScissor(x, y, widthViewport, heightViewport);
+            glViewport(x, y, widthViewport, heightViewport);
         }
     };
 
@@ -180,7 +197,7 @@ public class Engine {
         /*
         Engine Init
          */
-        Engine engine = new Engine(1280, 720, 9.0f / 16.0f);
+        Engine engine = new Engine(800, 600, 3.0f / 4.0f);
         int speed = 10; //vitesse déplacement Object
         engine.init();