16 bpp video stream capture, render and WebGL usage - Realsense R200 & SR300 support.

cc/output/shader.cc

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/output/shader.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 
@@ skipping 2110 matching lines @@
     });
   } else {
     get_alpha = SHADER0([]() {
       float GetAlpha(vec2 ya_clamped) { return alpha; }
     });
   }
 
   return FRAGMENT_SHADER(head, get_uv + get_alpha + main);
 }
 
+FragmentShaderYVideo::FragmentShaderYVideo()
+    : FragmentTexOpaqueBinding(),
+      x_derivative_location_(-1),
+      y_derivative_location_(-1) {}
+
+void FragmentShaderYVideo::Init(GLES2Interface* context,
+                                unsigned program,
+                                int* base_uniform_index) {
+  FragmentTexOpaqueBinding::Init(context, program, base_uniform_index);
+
+  static const char* uniforms[] = {"x_derivative", "y_derivative"};
+  int locations[arraysize(uniforms)];
+
+  GetProgramUniformLocations(context, program, arraysize(uniforms), uniforms,
+                             locations, base_uniform_index);
+  x_derivative_location_ = locations[0];
+  y_derivative_location_ = locations[1];
+}
+
+std::string FragmentShaderYVideo::GetShaderString(TexCoordPrecision precision,
+                                                  SamplerType sampler) const {
+  return FRAGMENT_SHADER(GetShaderHead(), GetShaderBody());
+}
+
+std::string FragmentShaderYVideo::GetShaderHead() {
+  return SHADER0([]() {
+    precision mediump float;
+    varying TexCoordPrecision vec2 v_texCoord;
+    uniform SamplerType s_texture;
+    uniform float x_derivative;
+    uniform float y_derivative;
+  });
+}
+
+std::string FragmentShaderYVideo::GetShaderBody() {
+  return SHADER0([]() {
+    vec4 TextureLookupBilinear(sampler2D sampler, highp vec2 texCoord) {
+      vec4 s1 = texture2D(sampler, texCoord);
+      vec4 s2 = texture2D(sampler, texCoord + vec2(x_derivative, 0.));
+      vec4 s3 = texture2D(sampler, texCoord + vec2(0., y_derivative));
+      vec4 s4 = texture2D(sampler, texCoord + vec2(x_derivative, y_derivative));
+      vec2 f = fract(texCoord.xy / vec2(x_derivative, y_derivative));
+      return mix(mix(s1, s2, f.x), mix(s3, s4, f.x), f.y);
+    }
+    void main() {
+      gl_FragColor =
+          vec4(vec3(TextureLookupBilinear(s_texture, v_texCoord).g), 1.);
+    }
+  });
+}
+
 FragmentShaderColor::FragmentShaderColor() : color_location_(-1) {
 }
 
 void FragmentShaderColor::Init(GLES2Interface* context,
                                unsigned program,
                                int* base_uniform_index) {
   static const char* uniforms[] = {
       "color",
   };
   int locations[arraysize(uniforms)];
@@ skipping 63 matching lines @@
     void main() {
       vec4 d4 = min(edge_dist[0], edge_dist[1]);
       vec2 d2 = min(d4.xz, d4.yw);
       float aa = clamp(gl_FragCoord.w * min(d2.x, d2.y), 0.0, 1.0);
       gl_FragColor = color * aa;
     }
   });
 }
 
 }  // namespace cc