initial commit, 4.5 stable

drivers/gles3/shaders/effects/glow.glsl

@@ -0,0 +1,113 @@
+/* clang-format off */
+#[modes]
+
+// Based on Dual filtering glow as explained in Marius Bjørge presentation at Siggraph 2015 "Bandwidth-Efficient Rendering"
+
+mode_filter = #define MODE_FILTER
+mode_downsample = #define MODE_DOWNSAMPLE
+mode_upsample = #define MODE_UPSAMPLE
+
+#[specializations]
+
+USE_MULTIVIEW = false
+
+#[vertex]
+layout(location = 0) in vec2 vertex_attrib;
+
+/* clang-format on */
+
+out vec2 uv_interp;
+
+void main() {
+	uv_interp = vertex_attrib * 0.5 + 0.5;
+	gl_Position = vec4(vertex_attrib, 1.0, 1.0);
+}
+
+/* clang-format off */
+#[fragment]
+/* clang-format on */
+
+#ifdef MODE_FILTER
+#ifdef USE_MULTIVIEW
+uniform sampler2DArray source_color; // texunit:0
+#else
+uniform sampler2D source_color; // texunit:0
+#endif // USE_MULTIVIEW
+uniform float view;
+uniform vec2 pixel_size;
+uniform float luminance_multiplier;
+uniform float glow_bloom;
+uniform float glow_hdr_threshold;
+uniform float glow_hdr_scale;
+uniform float glow_luminance_cap;
+#endif // MODE_FILTER
+
+#ifdef MODE_DOWNSAMPLE
+uniform sampler2D source_color; // texunit:0
+uniform vec2 pixel_size;
+#endif // MODE_DOWNSAMPLE
+
+#ifdef MODE_UPSAMPLE
+uniform sampler2D source_color; // texunit:0
+uniform vec2 pixel_size;
+#endif // MODE_UPSAMPLE
+
+in vec2 uv_interp;
+
+layout(location = 0) out vec4 frag_color;
+
+void main() {
+#ifdef MODE_FILTER
+	// Note, we read from an image with double resolution, so we average those out
+#ifdef USE_MULTIVIEW
+	vec2 half_pixel = pixel_size * 0.5;
+	vec3 uv = vec3(uv_interp, view);
+	vec3 color = textureLod(source_color, uv, 0.0).rgb * 4.0;
+	color += textureLod(source_color, uv - vec3(half_pixel, 0.0), 0.0).rgb;
+	color += textureLod(source_color, uv + vec3(half_pixel, 0.0), 0.0).rgb;
+	color += textureLod(source_color, uv - vec3(half_pixel.x, -half_pixel.y, 0.0), 0.0).rgb;
+	color += textureLod(source_color, uv + vec3(half_pixel.x, -half_pixel.y, 0.0), 0.0).rgb;
+#else
+	vec2 half_pixel = pixel_size * 0.5;
+	vec2 uv = uv_interp;
+	vec3 color = textureLod(source_color, uv, 0.0).rgb * 4.0;
+	color += textureLod(source_color, uv - half_pixel, 0.0).rgb;
+	color += textureLod(source_color, uv + half_pixel, 0.0).rgb;
+	color += textureLod(source_color, uv - vec2(half_pixel.x, -half_pixel.y), 0.0).rgb;
+	color += textureLod(source_color, uv + vec2(half_pixel.x, -half_pixel.y), 0.0).rgb;
+#endif // USE_MULTIVIEW
+	color /= luminance_multiplier * 8.0;
+
+	float feedback_factor = max(color.r, max(color.g, color.b));
+	float feedback = max(smoothstep(glow_hdr_threshold, glow_hdr_threshold + glow_hdr_scale, feedback_factor), glow_bloom);
+
+	color = min(color * feedback, vec3(glow_luminance_cap));
+
+	frag_color = vec4(luminance_multiplier * color, 1.0);
+#endif // MODE_FILTER
+
+#ifdef MODE_DOWNSAMPLE
+	vec2 half_pixel = pixel_size * 0.5;
+	vec4 color = textureLod(source_color, uv_interp, 0.0) * 4.0;
+	color += textureLod(source_color, uv_interp - half_pixel, 0.0);
+	color += textureLod(source_color, uv_interp + half_pixel, 0.0);
+	color += textureLod(source_color, uv_interp - vec2(half_pixel.x, -half_pixel.y), 0.0);
+	color += textureLod(source_color, uv_interp + vec2(half_pixel.x, -half_pixel.y), 0.0);
+	frag_color = color / 8.0;
+#endif // MODE_DOWNSAMPLE
+
+#ifdef MODE_UPSAMPLE
+	vec2 half_pixel = pixel_size * 0.5;
+
+	vec4 color = textureLod(source_color, uv_interp + vec2(-half_pixel.x * 2.0, 0.0), 0.0);
+	color += textureLod(source_color, uv_interp + vec2(-half_pixel.x, half_pixel.y), 0.0) * 2.0;
+	color += textureLod(source_color, uv_interp + vec2(0.0, half_pixel.y * 2.0), 0.0);
+	color += textureLod(source_color, uv_interp + vec2(half_pixel.x, half_pixel.y), 0.0) * 2.0;
+	color += textureLod(source_color, uv_interp + vec2(half_pixel.x * 2.0, 0.0), 0.0);
+	color += textureLod(source_color, uv_interp + vec2(half_pixel.x, -half_pixel.y), 0.0) * 2.0;
+	color += textureLod(source_color, uv_interp + vec2(0.0, -half_pixel.y * 2.0), 0.0);
+	color += textureLod(source_color, uv_interp + vec2(-half_pixel.x, -half_pixel.y), 0.0) * 2.0;
+
+	frag_color = color / 12.0;
+#endif // MODE_UPSAMPLE
+}