Taking care of glBlendEquation in 2.1

Author: codeanticode

android/core/src/processing/core/PGraphicsAndroid3D.java

@@ -345,6 +345,7 @@ public class PGraphicsAndroid3D extends PGraphics {
  static protected boolean matrixGetSupported;
  static protected boolean vboSupported;
  static protected boolean fboSupported;
+ static protected boolean blendEqSupported;
  static protected int maxTextureSize;
  static protected float maxPointSize;
  static protected float maxLineWidth;
@@ -2551,7 +2552,7 @@ protected void textLineImpl(char buffer[], int start, int stop, float x, float y
 
  if (!blend || blendMode != BLEND) {
  gl.glEnable(GL10.GL_BLEND);
- if (gl11xp != null) gl11xp.glBlendEquation(GL11ExtensionPack.GL_FUNC_ADD);
+ if (blendEqSupported) gl11xp.glBlendEquation(GL11ExtensionPack.GL_FUNC_ADD);
  gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA);
  }
 
@@ -4988,37 +4989,36 @@ public void blend(int mode) {
  blendMode = mode;
  gl.glEnable(GL10.GL_BLEND);
  if (mode == REPLACE) { 
- if (gl11xp != null) gl11xp.glBlendEquation(GL11ExtensionPack.GL_FUNC_ADD);
+ if (blendEqSupported) gl11xp.glBlendEquation(GL11ExtensionPack.GL_FUNC_ADD);
  gl.glBlendFunc(GL10.GL_ONE, GL10.GL_ZERO);
  } else if (mode == BLEND) {
- if (gl11xp != null) gl11xp.glBlendEquation(GL11ExtensionPack.GL_FUNC_ADD);
+ if (blendEqSupported) gl11xp.glBlendEquation(GL11ExtensionPack.GL_FUNC_ADD);
  gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA);
  } else if (mode == ADD) {
- if (gl11xp != null) gl11xp.glBlendEquation(GL11ExtensionPack.GL_FUNC_ADD);
+ if (blendEqSupported) gl11xp.glBlendEquation(GL11ExtensionPack.GL_FUNC_ADD);
  gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE);
  } else if (mode == MULTIPLY) {
- if (gl11xp != null) gl11xp.glBlendEquation(GL11ExtensionPack.GL_FUNC_ADD); 
+ if (blendEqSupported) gl11xp.glBlendEquation(GL11ExtensionPack.GL_FUNC_ADD); 
  gl.glBlendFunc(GL10.GL_DST_COLOR, GL10.GL_SRC_COLOR);
  } else if (mode == SUBTRACT) {
- if (gl11xp != null) gl11xp.glBlendEquation(GL11ExtensionPack.GL_FUNC_ADD); 
+ if (blendEqSupported) gl11xp.glBlendEquation(GL11ExtensionPack.GL_FUNC_ADD); 
  gl.glBlendFunc(GL10.GL_ONE_MINUS_DST_COLOR, GL10.GL_ZERO); 
  } else if (mode == DARKEST) {
- if (gl11xp != null) { 
+ if (blendEqSupported) { 
  gl11xp.glBlendEquation(GL_MIN_EXT); 
  gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_DST_ALPHA);
  } else {
  PGraphics.showWarning("A3D: This blend mode is currently unsupported."); 
  }
  } else if (mode == LIGHTEST) {
- if (gl11xp != null) { 
+ if (blendEqSupported) { 
  gl11xp.glBlendEquation(GL_MAX_EXT);
  gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_DST_ALPHA);
  } else {
  PGraphics.showWarning("A3D: This blend mode is currently unsupported.");
  }
-
  } else if (mode == DIFFERENCE) {
- if (gl11xp != null) {
+ if (blendEqSupported) {
  gl11xp.glBlendEquation(GL11ExtensionPack.GL_FUNC_REVERSE_SUBTRACT);
  gl.glBlendFunc(GL10.GL_ONE, GL10.GL_ONE);
  } else {
@@ -5189,7 +5189,20 @@ public void onSurfaceCreated(GL10 igl, EGLConfig config) {
  fboSupported = false;
  } 
  }
-
+ 
+ if (gl11xp != null) { 
+ try {
+ gl11xp.glBlendEquation(GL11ExtensionPack.GL_FUNC_ADD);
+ blendEqSupported = true;
+ } catch (UnsupportedOperationException e) {
+ // This takes care of Android 2.1 and older where the glBlendEquation is present in the API,
+ // but any call to it will result in an error.
+ blendEqSupported = false;
+ }
+ } else {
+ blendEqSupported = false;
+ }
+ 
  usingModelviewStack = gl11 == null || !matrixGetSupported;
 
  int temp[] = new int[2];