Add rescaling support

Author: riccardobl

jme3-android/src/main/java/com/jme3/app/AndroidHarness.java

@@ -494,6 +494,11 @@ public void reshape(int width, int height) {
         app.reshape(width, height);
     }
 
+    @Override
+    public void rescale(float x, float y) {
+        app.rescale(x, y);
+    }
+
     @Override
     public void update() {
         app.update();

jme3-android/src/main/java/com/jme3/app/AndroidHarnessFragment.java

@@ -571,6 +571,11 @@ public void reshape(int width, int height) {
         app.reshape(width, height);
     }
 
+    @Override
+    public void rescale(float x, float y) {
+        app.rescale(x, y);
+    }
+
     @Override
     public void update() {
         app.update();

jme3-android/src/main/java/com/jme3/app/jmeSurfaceView/JmeSurfaceView.java

@@ -395,6 +395,17 @@ public void reshape(int width, int height) {
         jmeSurfaceViewLogger.log(Level.INFO, "Requested reshaping from the system listener");
     }
 
+
+    @Override
+    public void rescale(float x, float y) {
+        if (legacyApplication == null) {
+            return;
+        }
+        legacyApplication.rescale(x, y);
+        jmeSurfaceViewLogger.log(Level.INFO, "Requested rescaling from the system listener");
+    }
+
+
     @Override
     public void update() {
         /*Invoking can be delayed by delaying the draw of GlSurfaceView component on the screen*/

jme3-core/src/main/java/com/jme3/app/LegacyApplication.java

@@ -578,6 +578,17 @@ public void reshape(int w, int h){
         }
     }
 
+
+    /**
+     * Internal use only.
+     */
+    @Override
+    public void rescale(float x, float y){
+        if (renderManager != null) {
+            renderManager.notifyRescale(x, y);
+        }
+    }
+
     /**
      * Restarts the context, applying any changed settings.
      * <p>

jme3-core/src/main/java/com/jme3/post/SceneProcessor.java

@@ -62,6 +62,17 @@ public interface SceneProcessor {
      */
     public void reshape(ViewPort vp, int w, int h);
 
+    /**
+     * Called when the scale of the viewport has been changed.
+     *
+     * @param vp the affected ViewPort
+     * @param x the new scale (in pixels)
+     * @param y the new scale (in pixels)
+     */
+    public default void rescale(ViewPort vp, float x, float y){
+
+    }
+
     /**
      * @return True if initialize() has been called on this SceneProcessor,
      * false if otherwise.

jme3-core/src/main/java/com/jme3/renderer/RenderManager.java

@@ -342,6 +342,17 @@ private void notifyReshape(ViewPort vp, int w, int h) {
         }
     }
 
+    private void notifyRescale(ViewPort vp, float x, float y) {
+        List<SceneProcessor> processors = vp.getProcessors();
+        for (SceneProcessor proc : processors) {
+            if (!proc.isInitialized()) {
+                proc.initialize(this, vp);
+            } else {
+                proc.rescale(vp, x, y);
+            }
+        }
+    }
+
     /**
      * Internal use only.
      * Updates the resolution of all on-screen cameras to match
@@ -374,6 +385,18 @@ public void notifyReshape(int w, int h) {
         }
     }
 
+    public void notifyRescale(float x, float y) {
+        for (ViewPort vp : preViewPorts) {
+            notifyRescale(vp, x, y);
+        }
+        for (ViewPort vp : viewPorts) {        
+            notifyRescale(vp, x, y);
+        }
+        for (ViewPort vp : postViewPorts) {
+            notifyRescale(vp, x, y);
+        }
+    }
+
     /**
      * Sets the material to use to render all future objects.
      * This overrides the material set on the geometry and renders

jme3-core/src/main/java/com/jme3/system/SystemListener.java

@@ -51,6 +51,14 @@ public interface SystemListener {
      */
     public void reshape(int width, int height);
 
+    /**
+     * Called to notify the application that the scale has changed.
+     * @param x the new scale of the display (in pixels, ≥0)
+     * @param y the new scale of the display (in pixels, ≥0)
+     */
+    public void rescale(float x, float y);
+
+
     /**
      * Callback to update the application state, and render the scene
      * to the back buffer.

jme3-desktop/src/main/java/com/jme3/system/awt/AwtPanelsContext.java

@@ -67,6 +67,11 @@ public void reshape(int width, int height) {
             throw new IllegalStateException();
         }
 
+        @Override
+        public void rescale(float x, float y) {
+            throw new IllegalStateException();
+        }
+
         @Override
         public void update() {
             updateInThread();

jme3-lwjgl3/src/main/java/com/jme3/system/lwjgl/LwjglWindow.java

@@ -279,6 +279,8 @@ public void invoke(int error, long description) {
 
         if (settings.getWindowWidth() <= 0 || settings.getWindowHeight() <= 0) {
             settings.setWindowSize(videoMode.width(), videoMode.height());
+        }else{
+            settings.setWindowSize(settings.getWindowWidth(), settings.getWindowHeight());
         }
 
         settings.setResolution(settings.getWindowWidth(), settings.getWindowHeight());// Assume default framebuffer size == window size
@@ -367,19 +369,24 @@ public void invoke(final long window, final int width, final int height) {
 
         updateDefaultFramebufferSize();
 
-        framesAfterContextStarted = 0;
     }
 
     private void updateDefaultFramebufferSize() {
         // If default framebuffer size is different than window size (eg. HiDPI)
         int[] width = new int[1];
         int[] height = new int[1];
         glfwGetFramebufferSize(window, width, height);
+
+        float[] xScale = new float[1];
+        float[] yScale = new float[1];
+        glfwGetWindowContentScale(window, xScale, yScale); 
+
         if (settings.getWidth() != width[0] || settings.getHeight() != height[0]) {
             settings.setResolution(width[0], height[0]);
             // https://www.glfw.org/docs/latest/window_guide.html#window_fbsize
+            listener.rescale(xScale[0],yScale[0]);
             listener.reshape(width[0], height[0]);
-        }
+        }   
     }
 
     private void onWindowSizeChanged(final int width, final int height) {
@@ -583,7 +590,6 @@ protected boolean initInThread() {
         return true;
     }
 
-    private int framesAfterContextStarted = 0;
 
     /**
      * execute one iteration of the render loop in the OpenGL thread