From e0c085413d848c9af458c510654fb06d4248f02f Mon Sep 17 00:00:00 2001
From: codeanticode <andres.colubri@gmail.com>
Date: Thu, 22 Mar 2012 17:56:22 +0000
Subject: [PATCH] Revised clear-buffer logic

---
 android/core/src/processing/core/PGL.java     | 31 ++++++-------------
 .../processing/core/PGraphicsAndroid3D.java   | 10 ++++--
 .../processing/opengl/PGraphicsOpenGL.java    | 10 ++++--
 3 files changed, 26 insertions(+), 25 deletions(-)

diff --git a/android/core/src/processing/core/PGL.java b/android/core/src/processing/core/PGL.java
index 1bb38d2dc..6daa63997 100644
--- a/android/core/src/processing/core/PGL.java
+++ b/android/core/src/processing/core/PGL.java
@@ -440,28 +440,14 @@ public class PGL {
       // Simplest scenario: clear mode means we clear both the color and depth buffers.
       // No need for saving front color buffer, etc.
       GLES20.glClearColor(0, 0, 0, 0);
-      GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);        
-    } else {
+      GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);      
+    }
+    
+    if (!clear) {
       GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, fbo[0]);    
       GLES20.glFramebufferTexture2D(GLES20.GL_FRAMEBUFFER, GLES20.GL_COLOR_ATTACHMENT0, GLES20.GL_TEXTURE_2D, textures[frontTex], 0);   
-
-      int status = glCheckFramebufferStatus(PGL.GL_FRAMEBUFFER);
-      if (status != PGL.GL_FRAMEBUFFER_COMPLETE) {        
-        if (status == PGL.GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT) {
-          throw new RuntimeException("PFramebuffer: GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT (" + Integer.toHexString(status) + ")");
-        } else if (status == PGL.GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT) {
-          throw new RuntimeException("PFramebuffer: GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT (" + Integer.toHexString(status) + ")");
-        } else if (status == PGL.GL_FRAMEBUFFER_INCOMPLETE_DIMENSIONS) {
-          throw new RuntimeException("PFramebuffer: GL_FRAMEBUFFER_INCOMPLETE_DIMENSIONS (" + Integer.toHexString(status) + ")");      
-        } else if (status == PGL.GL_FRAMEBUFFER_INCOMPLETE_FORMATS) {
-          throw new RuntimeException("PFramebuffer: GL_FRAMEBUFFER_INCOMPLETE_FORMATS (" + Integer.toHexString(status) + ")");
-        } else if (status == PGL.GL_FRAMEBUFFER_UNSUPPORTED) {
-          throw new RuntimeException("PFramebuffer: GL_FRAMEBUFFER_UNSUPPORTED" + Integer.toHexString(status));      
-        } else {
-          throw new RuntimeException("PFramebuffer: unknown framebuffer error (" + Integer.toHexString(status) + ")");
-        }      
-      }
-       
+      validateFramebuffer();
+      
       // We need to save the color buffer after finishing with the rendering of this frame,
       // to use is as the background for the next frame ("incremental drawing"). 
       GLES20.glClearColor(0, 0, 0, 0);
@@ -469,12 +455,15 @@ public class PGL {
       if (firstOnscreenFrame) {
         // No need to draw back color buffer because we are in the first frame.
         GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
-        firstOnscreenFrame = false;
       } else {
         // Render previous draw texture as background.      
         drawTexture(GLES20.GL_TEXTURE_2D, textures[backTex], texWidth, texHeight, 0, 0, pg.width, pg.height, 0, 0, pg.width, pg.height);
       }
     }
+    
+    if (firstOnscreenFrame) {
+      firstOnscreenFrame = false;
+    }
   }
   
   
diff --git a/android/core/src/processing/core/PGraphicsAndroid3D.java b/android/core/src/processing/core/PGraphicsAndroid3D.java
index 347ba3578..5324e2d22 100644
--- a/android/core/src/processing/core/PGraphicsAndroid3D.java
+++ b/android/core/src/processing/core/PGraphicsAndroid3D.java
@@ -1748,6 +1748,8 @@ public class PGraphicsAndroid3D extends PGraphics {
 
     manipulatingCamera = false;
         
+    clearColorBuffer = false;
+    
     if (fbStack == null) {
       fbStack = new Stack<PFramebuffer>();
 
@@ -4352,7 +4354,9 @@ public class PGraphicsAndroid3D extends PGraphics {
   protected void backgroundImpl(PImage image) {
     backgroundImpl();
     set(0, 0, image);
-    clearColorBuffer = true;
+    if (0 < parent.frameCount) {
+      clearColorBuffer = true;
+    }
   }
 
   
@@ -4371,7 +4375,9 @@ public class PGraphicsAndroid3D extends PGraphics {
     
     pgl.glClearColor(backgroundR, backgroundG, backgroundB, 1);
     pgl.glClear(PGL.GL_COLOR_BUFFER_BIT);
-    clearColorBuffer = true;
+    if (0 < parent.frameCount) {
+      clearColorBuffer = true;
+    }
   }  
   
   
diff --git a/java/libraries/opengl/src/processing/opengl/PGraphicsOpenGL.java b/java/libraries/opengl/src/processing/opengl/PGraphicsOpenGL.java
index be58f55e4..054ba335e 100644
--- a/java/libraries/opengl/src/processing/opengl/PGraphicsOpenGL.java
+++ b/java/libraries/opengl/src/processing/opengl/PGraphicsOpenGL.java
@@ -1754,6 +1754,8 @@ public class PGraphicsOpenGL extends PGraphics {
 
     manipulatingCamera = false;
         
+    clearColorBuffer = false;
+    
     if (fbStack == null) {
       fbStack = new Stack<PFramebuffer>();
 
@@ -4358,7 +4360,9 @@ public class PGraphicsOpenGL extends PGraphics {
   protected void backgroundImpl(PImage image) {
     backgroundImpl();
     set(0, 0, image);
-    clearColorBuffer = true;
+    if (0 < parent.frameCount) {
+      clearColorBuffer = true;
+    }
   }
 
   
@@ -4377,7 +4381,9 @@ public class PGraphicsOpenGL extends PGraphics {
     
     pgl.glClearColor(backgroundR, backgroundG, backgroundB, 1);
     pgl.glClear(PGL.GL_COLOR_BUFFER_BIT);
-    clearColorBuffer = true;
+    if (0 < parent.frameCount) {
+      clearColorBuffer = true;
+    }
   }