1 files changed, 71 insertions, 0 deletions
diff --git a/js/shader.js b/js/shader.js
new file mode 100644
index 0000000..2f5fda1
--- /dev/null
+++ b/js/shader.js
@@ -0,0 +1,71 @@
+var shader_build = function(){
+  var fn_str = document.getElementById('shader').value
+  if (!fn_str.length) return
+  try {
+    var fn = new Function('x','y','t','d', fn_str)
+    shader = fn
+    shade = shade_error_handling
+  } catch (e) {
+    throw Error ("Shader compilation error")
+  }
+}
+
+var r,g,b,a;
+
+function shade_no_error_handling(frame, t){
+  if (! t || isNaN(t)) throw Error ("No time specified")
+  if (! frame) throw Error ("No frame specified")
+
+  var imgData = frame.ctx.getImageData(0,0,w,h)
+  var data = imgData.data
+  var clone = frame.cloneData.data  
+  var realw = w, realh = h, v, index
+
+  for (var x = 0; x < w; x++) {
+    for (var y = 0; y < h; y++) {
+      q = 4*(y*w+x)
+      r = data[q], g = data[q+1], b = data[q+2], a = data[q+3]
+      result = shader(x,y,t,clone)
+      data[q] = r
+      data[q+1] = g
+      data[q+2] = b
+      data[q+3] = a
+      w = realw, h = realh
+    }
+  }
+  cc.putImageData(imgData,0,0)
+}
+
+function shade_error_handling(frame, t){
+  if (! t || isNaN(t)) throw Error ("No time specified")
+  if (! frame) throw Error ("No frame specified")
+
+  var imgData = frame.ctx.getImageData(0,0,w,h)
+  var data = imgData.data
+  var clone = frame.cloneData.data
+
+  try {
+    var realw = w, realh = h, v, index
+
+    for (var x = 0; x < w; x++) {
+      for (var y = 0; y < h; y++) {
+        q = 4*(y*w+x)
+        r = data[q], g = data[q+1], b = data[q+2], a = data[q+3]
+        result = shader(x,y,t,clone)
+        data[q] = r
+        data[q+1] = g
+        data[q+2] = b
+        data[q+3] = a
+        w = realw, h = realh
+      }
+    }
+  }
+  catch(e){
+    // console.log(e.stack)
+    throw Error ("Shader execution error")
+  }
+  cc.putImageData(imgData,0,0)
+  shade = shade_no_error_handling
+}
+
+shade = shade_error_handling