From 7ecabd8a346fddb73dc8702ad31b7a32289a5353 Mon Sep 17 00:00:00 2001
From: codeanticode <andres.colubri@gmail.com>
Date: Fri, 5 Jun 2015 18:57:17 -0400
Subject: [PATCH] init shader in shader() call

---
 .../processing/opengl/PGraphicsOpenGL.java    |  8 +-
 core/src/processing/opengl/PShader.java       | 88 ++++++++++++-------
 2 files changed, 59 insertions(+), 37 deletions(-)

diff --git a/core/src/processing/opengl/PGraphicsOpenGL.java b/core/src/processing/opengl/PGraphicsOpenGL.java
index 29c8e2b45..ae57241d9 100644
--- a/core/src/processing/opengl/PGraphicsOpenGL.java
+++ b/core/src/processing/opengl/PGraphicsOpenGL.java
@@ -6850,15 +6850,15 @@ public class PGraphicsOpenGL extends PGraphics {
 
   @Override
   public PShader loadShader(String fragFilename, String vertFilename) {
+    PShader shader = null;
     if (fragFilename == null || fragFilename.equals("")) {
       PGraphics.showWarning(MISSING_FRAGMENT_SHADER);
-      return null;
     } else if (vertFilename == null || vertFilename.equals("")) {
       PGraphics.showWarning(MISSING_VERTEX_SHADER);
-      return null;
     } else {
-      return new PShader(parent, vertFilename, fragFilename);
+      shader = new PShader(parent, vertFilename, fragFilename);
     }
+    return shader;
   }
 
 
@@ -6866,6 +6866,7 @@ public class PGraphicsOpenGL extends PGraphics {
   public void shader(PShader shader) {
     flush(); // Flushing geometry drawn with a different shader.
 
+    if (shader != null) shader.init();
     if (shader.isPolyShader()) polyShader = shader;
     else if (shader.isLineShader()) lineShader = shader;
     else if (shader.isPointShader()) pointShader = shader;
@@ -6877,6 +6878,7 @@ public class PGraphicsOpenGL extends PGraphics {
   public void shader(PShader shader, int kind) {
     flush(); // Flushing geometry drawn with a different shader.
 
+    if (shader != null) shader.init();
     if (kind == TRIANGLES) polyShader = shader;
     else if (kind == LINES) lineShader = shader;
     else if (kind == POINTS) pointShader = shader;
diff --git a/core/src/processing/opengl/PShader.java b/core/src/processing/opengl/PShader.java
index aad807194..03a5f6c4f 100644
--- a/core/src/processing/opengl/PShader.java
+++ b/core/src/processing/opengl/PShader.java
@@ -753,7 +753,7 @@ public class PShader implements PConstants {
       uniformValues.put(loc, new UniformValue(type, value));
     } else {
       PGraphics.showWarning("The shader doesn't have a uniform called \"" +
-                            name + "\" OR the uniform was removed during" +
+                            name + "\" OR the uniform was removed during " +
                             "compilation because it was unused.");
     }
   }
@@ -897,51 +897,67 @@ public class PShader implements PConstants {
     }
   }
 
-  protected void init() {
+
+  public void init() {
     if (glProgram == 0 || contextIsOutdated()) {
-      context = pgl.getCurrentContext();
-      glProgram = PGraphicsOpenGL.createGLSLProgramObject(context, pgl);
-
-      boolean vertRes = true;
-      if (hasVertexShader()) {
-        vertRes = compileVertexShader();
-      } else {
-        PGraphics.showException("Doesn't have a vertex shader");
-      }
-
-      boolean fragRes = true;
-      if (hasFragmentShader()) {
-        fragRes = compileFragmentShader();
-      } else {
-        PGraphics.showException("Doesn't have a fragment shader");
-      }
-
-      if (vertRes && fragRes) {
+      create();
+      if (compile()) {
         pgl.attachShader(glProgram, glVertex);
         pgl.attachShader(glProgram, glFragment);
+
         setup();
 
         pgl.linkProgram(glProgram);
 
-        pgl.getProgramiv(glProgram, PGL.LINK_STATUS, intBuffer);
-        boolean linked = intBuffer.get(0) == 0 ? false : true;
-        if (!linked) {
-          PGraphics.showException("Cannot link shader program:\n" +
-                                  pgl.getProgramInfoLog(glProgram));
-        }
-
-        pgl.validateProgram(glProgram);
-        pgl.getProgramiv(glProgram, PGL.VALIDATE_STATUS, intBuffer);
-        boolean validated = intBuffer.get(0) == 0 ? false : true;
-        if (!validated) {
-          PGraphics.showException("Cannot validate shader program:\n" +
-                                  pgl.getProgramInfoLog(glProgram));
-        }
+        validate();
       }
     }
   }
 
 
+  protected void create() {
+    context = pgl.getCurrentContext();
+    glProgram = PGraphicsOpenGL.createGLSLProgramObject(context, pgl);
+  }
+
+
+  protected boolean compile() {
+    boolean vertRes = true;
+    if (hasVertexShader()) {
+      vertRes = compileVertexShader();
+    } else {
+      PGraphics.showException("Doesn't have a vertex shader");
+    }
+
+    boolean fragRes = true;
+    if (hasFragmentShader()) {
+      fragRes = compileFragmentShader();
+    } else {
+      PGraphics.showException("Doesn't have a fragment shader");
+    }
+
+    return vertRes && fragRes;
+  }
+
+
+  protected void validate() {
+    pgl.getProgramiv(glProgram, PGL.LINK_STATUS, intBuffer);
+    boolean linked = intBuffer.get(0) == 0 ? false : true;
+    if (!linked) {
+      PGraphics.showException("Cannot link shader program:\n" +
+                              pgl.getProgramInfoLog(glProgram));
+    }
+
+    pgl.validateProgram(glProgram);
+    pgl.getProgramiv(glProgram, PGL.VALIDATE_STATUS, intBuffer);
+    boolean validated = intBuffer.get(0) == 0 ? false : true;
+    if (!validated) {
+      PGraphics.showException("Cannot validate shader program:\n" +
+                              pgl.getProgramInfoLog(glProgram));
+    }
+  }
+
+
   protected boolean contextIsOutdated() {
     boolean outdated = !pgl.contextIsCurrent(context);
     if (outdated) {
@@ -962,10 +978,12 @@ public class PShader implements PConstants {
     return vertexShaderSource != null && 0 < vertexShaderSource.length;
   }
 
+
   protected boolean hasFragmentShader() {
     return fragmentShaderSource != null && 0 < fragmentShaderSource.length;
   }
 
+
   /**
    * @param shaderSource a string containing the shader's code
    */
@@ -1023,6 +1041,7 @@ public class PShader implements PConstants {
     }
   }
 
+
   static protected int getShaderType(String[] source, int defaultType) {
     for (int i = 0; i < source.length; i++) {
       String line = source[i].trim();
@@ -1220,6 +1239,7 @@ public class PShader implements PConstants {
     }
   }
 
+
   protected void bindTyped() {
     if (currentPG == null) {
       setRenderer(primaryPG.getCurrentPG());