1 files changed, 172 insertions, 0 deletions
diff --git a/drivers/gles3/shaders/subsurf_scattering.glsl b/drivers/gles3/shaders/subsurf_scattering.glsl
new file mode 100644
index 0000000000..89e618b66c
--- /dev/null
+++ b/drivers/gles3/shaders/subsurf_scattering.glsl
@@ -0,0 +1,172 @@
+[vertex]
+
+
+layout(location=0) in highp vec4 vertex_attrib;
+layout(location=4) in vec2 uv_in;
+
+out vec2 uv_interp;
+
+
+void main() {
+
+	uv_interp = uv_in;
+	gl_Position = vertex_attrib;
+}
+
+[fragment]
+
+//#define QUALIFIER uniform // some guy on the interweb says it may be faster with this
+#define QUALIFIER const
+
+#ifdef USE_25_SAMPLES
+
+const int kernel_size=25;
+QUALIFIER vec4 kernel[25] = vec4[] (
+    vec4(0.530605, 0.613514, 0.739601, 0.0),
+    vec4(0.000973794, 1.11862e-005, 9.43437e-007, -3.0),
+    vec4(0.00333804, 7.85443e-005, 1.2945e-005, -2.52083),
+    vec4(0.00500364, 0.00020094, 5.28848e-005, -2.08333),
+    vec4(0.00700976, 0.00049366, 0.000151938, -1.6875),
+    vec4(0.0094389, 0.00139119, 0.000416598, -1.33333),
+    vec4(0.0128496, 0.00356329, 0.00132016, -1.02083),
+    vec4(0.017924, 0.00711691, 0.00347194, -0.75),
+    vec4(0.0263642, 0.0119715, 0.00684598, -0.520833),
+    vec4(0.0410172, 0.0199899, 0.0118481, -0.333333),
+    vec4(0.0493588, 0.0367726, 0.0219485, -0.1875),
+    vec4(0.0402784, 0.0657244, 0.04631, -0.0833333),
+    vec4(0.0211412, 0.0459286, 0.0378196, -0.0208333),
+    vec4(0.0211412, 0.0459286, 0.0378196, 0.0208333),
+    vec4(0.0402784, 0.0657244, 0.04631, 0.0833333),
+    vec4(0.0493588, 0.0367726, 0.0219485, 0.1875),
+    vec4(0.0410172, 0.0199899, 0.0118481, 0.333333),
+    vec4(0.0263642, 0.0119715, 0.00684598, 0.520833),
+    vec4(0.017924, 0.00711691, 0.00347194, 0.75),
+    vec4(0.0128496, 0.00356329, 0.00132016, 1.02083),
+    vec4(0.0094389, 0.00139119, 0.000416598, 1.33333),
+    vec4(0.00700976, 0.00049366, 0.000151938, 1.6875),
+    vec4(0.00500364, 0.00020094, 5.28848e-005, 2.08333),
+    vec4(0.00333804, 7.85443e-005, 1.2945e-005, 2.52083),
+    vec4(0.000973794, 1.11862e-005, 9.43437e-007, 3.0)
+);
+
+#endif //USE_25_SAMPLES
+
+#ifdef USE_17_SAMPLES
+
+const int kernel_size=17;
+
+QUALIFIER vec4 kernel[17] = vec4[](
+    vec4(0.536343, 0.624624, 0.748867, 0.0),
+    vec4(0.00317394, 0.000134823, 3.77269e-005, -2.0),
+    vec4(0.0100386, 0.000914679, 0.000275702, -1.53125),
+    vec4(0.0144609, 0.00317269, 0.00106399, -1.125),
+    vec4(0.0216301, 0.00794618, 0.00376991, -0.78125),
+    vec4(0.0347317, 0.0151085, 0.00871983, -0.5),
+    vec4(0.0571056, 0.0287432, 0.0172844, -0.28125),
+    vec4(0.0582416, 0.0659959, 0.0411329, -0.125),
+    vec4(0.0324462, 0.0656718, 0.0532821, -0.03125),
+    vec4(0.0324462, 0.0656718, 0.0532821, 0.03125),
+    vec4(0.0582416, 0.0659959, 0.0411329, 0.125),
+    vec4(0.0571056, 0.0287432, 0.0172844, 0.28125),
+    vec4(0.0347317, 0.0151085, 0.00871983, 0.5),
+    vec4(0.0216301, 0.00794618, 0.00376991, 0.78125),
+    vec4(0.0144609, 0.00317269, 0.00106399, 1.125),
+    vec4(0.0100386, 0.000914679, 0.000275702, 1.53125),
+    vec4(0.00317394, 0.000134823, 3.77269e-005, 2.0)
+);
+
+#endif //USE_17_SAMPLES
+
+
+#ifdef USE_11_SAMPLES
+
+const int kernel_size=11;
+
+QUALIFIER vec4 kernel[11] = vec4[](
+    vec4(0.560479, 0.669086, 0.784728, 0.0),
+    vec4(0.00471691, 0.000184771, 5.07566e-005, -2.0),
+    vec4(0.0192831, 0.00282018, 0.00084214, -1.28),
+    vec4(0.03639, 0.0130999, 0.00643685, -0.72),
+    vec4(0.0821904, 0.0358608, 0.0209261, -0.32),
+    vec4(0.0771802, 0.113491, 0.0793803, -0.08),
+    vec4(0.0771802, 0.113491, 0.0793803, 0.08),
+    vec4(0.0821904, 0.0358608, 0.0209261, 0.32),
+    vec4(0.03639, 0.0130999, 0.00643685, 0.72),
+    vec4(0.0192831, 0.00282018, 0.00084214, 1.28),
+    vec4(0.00471691, 0.000184771, 5.07565e-005, 2.0)
+);
+
+#endif //USE_11_SAMPLES
+
+
+uniform float max_radius;
+uniform float fovy;
+uniform float camera_z_far;
+uniform float camera_z_near;
+uniform vec2 dir;
+in vec2 uv_interp;
+
+uniform sampler2D source_diffuse; //texunit:0
+uniform highp usampler2D source_motion_ss; //texunit:1
+uniform sampler2D source_depth; //texunit:2
+
+layout(location = 0) out vec4 frag_color;
+
+void main() {
+
+	float strength = float(texture(source_motion_ss,uv_interp).r>>24)*(1.0/255.0);
+	strength*=strength; //stored as sqrt
+
+	// Fetch color of current pixel:
+	vec4 base_color = texture(source_diffuse, uv_interp);
+
+	if (strength>0.0) {
+
+
+		// Fetch linear depth of current pixel:
+		float depth = texture(source_depth, uv_interp).r * 2.0 - 1.0;
+		depth = 2.0 * camera_z_near * camera_z_far / (camera_z_far + camera_z_near - depth * (camera_z_far - camera_z_near));
+		depth=-depth;
+
+
+		// Calculate the radius scale (1.0 for a unit plane sitting on the
+		// projection window):
+		float distance = 1.0 / tan(0.5 * fovy);
+		float scale = distance / -depth; //remember depth is negative by default in OpenGL
+
+		// Calculate the final step to fetch the surrounding pixels:
+		vec2 step = max_radius * scale * dir;
+		step *= strength; // Modulate it using the alpha channel.
+		step *= 1.0 / 3.0; // Divide by 3 as the kernels range from -3 to 3.
+
+		// Accumulate the center sample:
+		vec3 color_accum = base_color.rgb;
+		color_accum *= kernel[0].rgb;
+
+		// Accumulate the other samples:
+		for (int i = 1; i < kernel_size; i++) {
+			// Fetch color and depth for current sample:
+			vec2 offset = uv_interp + kernel[i].a * step;
+			vec3 color = texture(source_diffuse, offset).rgb;
+
+#ifdef ENABLE_FOLLOW_SURFACE
+			// If the difference in depth is huge, we lerp color back to "colorM":
+			float depth_cmp = texture(source_depth, offset).r *2.0 - 1.0;
+			depth_cmp = 2.0 * camera_z_near * camera_z_far / (camera_z_far + camera_z_near - depth_cmp * (camera_z_far - camera_z_near));
+			depth_cmp=-depth_cmp;
+
+			float s = clamp(300.0f * distance *
+					       max_radius * abs(depth - depth_cmp),0.0,1.0);
+			color = mix(color, base_color.rgb, s);
+#endif
+
+			// Accumulate:
+			color_accum += kernel[i].rgb * color;
+		}
+
+		frag_color = vec4(color_accum,base_color.a); //keep alpha (used for SSAO)
+	} else {
+		frag_color = base_color;
+	}
+}
+