ShaderCode: Add defaultShaderCustomization(..) to prelude shader source w/ GLSL version and default precision (if GLES) - Used by GearsES2/RedSquare/PointDemo (Made GLSL version proof)

2 files changed, 35 insertions, 4 deletions

diff --git a/src/jogl/classes/com/jogamp/opengl/util/glsl/ShaderCode.java b/src/jogl/classes/com/jogamp/opengl/util/glsl/ShaderCode.java
index f6b686d7e..378167c2c 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/glsl/ShaderCode.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/glsl/ShaderCode.java
@@ -46,6 +46,7 @@ import java.util.Set;
 import javax.media.opengl.GL;
 import javax.media.opengl.GL2ES2;
 import javax.media.opengl.GLES2;
+import javax.media.opengl.GLContext;
 import javax.media.opengl.GLException;
 
 import jogamp.opengl.Debug;
@@ -806,6 +807,34 @@ public class ShaderCode {
         }
     }
 
+    /** {@value #es2_default_precision_vp} */
+    public static final String es2_default_precision_vp = "\nprecision highp float;\nprecision highp int;\n";
+    /** {@value #es2_default_precision_fp} */
+    public static final String es2_default_precision_fp = "\nprecision mediump float;\nprecision mediump int;\n/*precision lowp sampler2D;*/\n";
+    
+    /**
+     * Default customization of this shader source code.
+     * <p>
+     * Note: The shader source to be edit must be created using a mutable StringBuilder.
+     * </p>
+     * @param gl a GL context, which must have been made current once 
+     * @param preludeVersion if true {@link GLContext#getGLSLVersionString()} is preluded, otherwise not.
+     * @param es2DefaultPrecision optional default precision source code line(s) preluded if not null and if {@link GL#isGLES()}.
+     *        You may use {@link #es2_default_precision_fp} for fragment shader and {@link #es2_default_precision_vp} for vertex shader.
+     * @return the index after the inserted data, maybe 0 if nothing has be inserted.
+     */
+    public final int defaultShaderCustomization(GL2ES2 gl, boolean preludeVersion, String es2DefaultPrecision) {
+        int pos = 0;
+        if(preludeVersion) {
+            final String glslVersion_prelude = gl.getContext().getGLSLVersionString();
+            pos = insertShaderSource(0, pos, glslVersion_prelude);
+        }
+        if( gl.isGLES() && null != es2DefaultPrecision ) {
+            pos = insertShaderSource(0, pos, es2DefaultPrecision);
+        }
+        return pos;
+    }    
+    
     //----------------------------------------------------------------------
     // Internals only below this point
     //
diff --git a/src/jogl/classes/com/jogamp/opengl/util/glsl/ShaderUtil.java b/src/jogl/classes/com/jogamp/opengl/util/glsl/ShaderUtil.java
index 8c0addb78..5afc5e38c 100644
--- a/src/jogl/classes/com/jogamp/opengl/util/glsl/ShaderUtil.java
+++ b/src/jogl/classes/com/jogamp/opengl/util/glsl/ShaderUtil.java
@@ -162,7 +162,8 @@ public class ShaderUtil {
                 try {
                     final int[] param = new int[1];
                     gl.glGetIntegerv(GL2ES2.GL_NUM_SHADER_BINARY_FORMATS, param, 0);
-                    int numFormats = param[0];
+                    final int err = gl.glGetError();
+                    final int numFormats = GL.GL_NO_ERROR == err ? param[0] : 0;
                     if(numFormats>0) {
                         int[] formats = new int[numFormats];
                         gl.glGetIntegerv(GL2ES2.GL_SHADER_BINARY_FORMATS, formats, 0);
@@ -170,7 +171,7 @@ public class ShaderUtil {
                             info.shaderBinaryFormats.add(new Integer(formats[i]));
                         }
                     }
-                } catch (GLException gle) { gle.printStackTrace(); }                    
+                } catch (GLException gle) { System.err.println("Catched Exception: "+gle.getMessage()); gle.printStackTrace(); }                    
             }
         }
         return info.shaderBinaryFormats;
@@ -186,7 +187,8 @@ public class ShaderUtil {
                 try {
                     final byte[] param = new byte[1];
                     gl.glGetBooleanv(GL2ES2.GL_SHADER_COMPILER, param, 0);
-                    boolean v = param[0]!=(byte)0x00;
+                    final int err = gl.glGetError();
+                    boolean v = GL.GL_NO_ERROR == err && param[0]!=(byte)0x00;
                     if(!v) {
                         final Set<Integer> bfs = getShaderBinaryFormats(gl);
                         if(bfs.size()==0) {
@@ -196,7 +198,7 @@ public class ShaderUtil {
                     }
                     info.shaderCompilerAvailable = new Boolean(v);
                     queryOK = true;
-                } catch (GLException gle) { gle.printStackTrace(); }
+                } catch (GLException gle) { System.err.println("Catched Exception: "+gle.getMessage()); gle.printStackTrace(); }
                 if(!queryOK) {
                     info.shaderCompilerAvailable = new Boolean(true);
                 }