o3d-webgl: vertex shader and vertex animation demo

samples/shaders/phong-vertex-anim-glsl.shader

+/*
+ * Copyright 2009, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+// This shader expects to be passed vertices that are part of an x-z plane mesh
+// because it assumes the normal for each vertex before being offset by the
+// animation is 0, 1, 0.
+
+uniform mat4 viewProjection;
+uniform mat4 world;
+uniform mat4 worldInverseTranspose;
+uniform float time;
+
+attribute vec4 position;
+
+varying vec3 v_normal;
+varying vec3 v_worldPosition;
+
+void main() {
+  vec3 worldPosition = (world * position).xyz;
+
+  float animValue = time + (worldPosition.x + worldPosition.z) * 0.4;
+  float animSin = sin(animValue);
+  float animCos = cos(animValue);
+  vec4 position = vec4(
+      worldPosition.x,
+      worldPosition.y + animSin,
+      worldPosition.z,
+      1);
+  gl_Position = viewProjection * position;
+  vec3 normalTmp = normalize(vec3(animCos, abs(animSin), animCos));
+  v_normal = (worldInverseTranspose * vec4(normalTmp, 0)).xyz;
+  v_worldPosition = position.xyz;
+}
+
+// #o3d SplitMarker
+
+uniform vec3 lightWorldPos;
+uniform vec4 lightIntensity;
+uniform vec4 ambientIntensity;
+uniform vec4 emissive;
+uniform vec4 ambient;
+uniform vec4 diffuse;
+uniform vec4 specular;
+uniform float shininess;
+uniform float time;
+uniform mat4 viewInverse;
+
+varying vec3 v_normal;
+varying vec3 v_worldPosition;
+
+vec4 lit(float l ,float h, float m) {
+  return vec4(1.0,
+              max(l, 0.0),
+              (l > 0.0) ? pow(max(0.0, h), m) : 0.0,
+              1.0);
+}
+
+void main() {
+  vec3 surfaceToLight = normalize(lightWorldPos - v_worldPosition);
+  vec3 worldNormal = normalize(v_normal);
+  vec3 surfaceToView = normalize(viewInverse[3].xyz - v_worldPosition);
+  vec3 halfVector = normalize(surfaceToLight + surfaceToView);
+  vec4 litResult = lit(dot(worldNormal, surfaceToLight),
+                         dot(worldNormal, halfVector), shininess);
+  vec4 outColor = ambientIntensity * ambient;
+  outColor += lightIntensity * (diffuse * litResult.y +
+      specular * litResult.z);
+  outColor += emissive;
+  gl_FragColor = vec4(outColor.rgb, diffuse.a);
+}
+
+// #o3d MatrixLoadOrder RowMajor