initial commit, 4.5 stable

servers/rendering/renderer_rd/shaders/effects/smaa_blending.glsl

@@ -0,0 +1,150 @@
+/**
+ * Copyright (C) 2013 Jorge Jimenez (jorge@iryoku.com)
+ * Copyright (C) 2013 Jose I. Echevarria (joseignacioechevarria@gmail.com)
+ * Copyright (C) 2013 Belen Masia (bmasia@unizar.es)
+ * Copyright (C) 2013 Fernando Navarro (fernandn@microsoft.com)
+ * Copyright (C) 2013 Diego Gutierrez (diegog@unizar.es)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is furnished to
+ * do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software. As clarification, there
+ * is no requirement that the copyright notice and permission be included in
+ * binary distributions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#[vertex]
+#version 450
+
+layout(location = 0) out vec2 tex_coord;
+layout(location = 1) out vec4 offset;
+
+layout(push_constant, std430) uniform Params {
+	vec2 inv_size;
+	vec2 pad;
+}
+params;
+
+void main() {
+	vec2 vertex_base;
+	if (gl_VertexIndex == 0) {
+		vertex_base = vec2(-1.0, -1.0);
+	} else if (gl_VertexIndex == 1) {
+		vertex_base = vec2(-1.0, 3.0);
+	} else {
+		vertex_base = vec2(3.0, -1.0);
+	}
+	gl_Position = vec4(vertex_base, 0.0, 1.0);
+	tex_coord = clamp(vertex_base, vec2(0.0, 0.0), vec2(1.0, 1.0)) * 2.0; // saturate(x) * 2.0
+	offset = fma(params.inv_size.xyxy, vec4(1.0, 0.0, 0.0, 1.0), tex_coord.xyxy);
+}
+
+#[fragment]
+#version 450
+
+layout(location = 0) in vec2 tex_coord;
+layout(location = 1) in vec4 offset;
+layout(set = 0, binding = 0) uniform sampler2D color_tex;
+layout(set = 1, binding = 0) uniform sampler2D blend_tex;
+
+layout(location = 0) out vec4 out_color;
+
+#define FLAG_USE_8_BIT_DEBANDING (1 << 0)
+#define FLAG_USE_10_BIT_DEBANDING (1 << 1)
+
+layout(push_constant, std430) uniform Params {
+	vec2 inv_size;
+	uint flags;
+	float pad;
+}
+params;
+
+#define textureLinear(tex, uv) srgb_to_linear(textureLod(tex, uv, 0.0).rgb)
+
+vec3 linear_to_srgb(vec3 color) {
+	// If going to srgb, clamp from 0 to 1.
+	color = clamp(color, vec3(0.0), vec3(1.0));
+	const vec3 a = vec3(0.055f);
+	return mix((vec3(1.0f) + a) * pow(color.rgb, vec3(1.0f / 2.4f)) - a, 12.92f * color.rgb, lessThan(color.rgb, vec3(0.0031308f)));
+}
+
+vec3 srgb_to_linear(vec3 color) {
+	return mix(pow((color.rgb + vec3(0.055)) * (1.0 / (1.0 + 0.055)), vec3(2.4)), color.rgb * (1.0 / 12.92), lessThan(color.rgb, vec3(0.04045)));
+}
+
+void SMAAMovc(bvec2 cond, inout vec2 variable, vec2 value) {
+	if (cond.x) {
+		variable.x = value.x;
+	}
+	if (cond.y) {
+		variable.y = value.y;
+	}
+}
+
+void SMAAMovc(bvec4 cond, inout vec4 variable, vec4 value) {
+	SMAAMovc(cond.xy, variable.xy, value.xy);
+	SMAAMovc(cond.zw, variable.zw, value.zw);
+}
+
+// From https://alex.vlachos.com/graphics/Alex_Vlachos_Advanced_VR_Rendering_GDC2015.pdf
+// and https://www.shadertoy.com/view/MslGR8 (5th one starting from the bottom)
+// NOTE: `frag_coord` is in pixels (i.e. not normalized UV).
+// This dithering must be applied after encoding changes (linear/nonlinear) have been applied
+// as the final step before quantization from floating point to integer values.
+vec3 screen_space_dither(vec2 frag_coord, float bit_alignment_diviser) {
+	// Iestyn's RGB dither (7 asm instructions) from Portal 2 X360, slightly modified for VR.
+	// Removed the time component to avoid passing time into this shader.
+	vec3 dither = vec3(dot(vec2(171.0, 231.0), frag_coord));
+	dither.rgb = fract(dither.rgb / vec3(103.0, 71.0, 97.0));
+
+	// Subtract 0.5 to avoid slightly brightening the whole viewport.
+	// Use a dither strength of 100% rather than the 37.5% suggested by the original source.
+	return (dither.rgb - 0.5) / bit_alignment_diviser;
+}
+
+void main() {
+	vec4 a;
+	a.x = texture(blend_tex, offset.xy).a;
+	a.y = texture(blend_tex, offset.zw).g;
+	a.wz = texture(blend_tex, tex_coord).xz;
+
+	if (dot(a, vec4(1.0, 1.0, 1.0, 1.0)) < 1e-5) {
+		out_color = textureLod(color_tex, tex_coord, 0.0);
+	} else {
+		bool h = max(a.x, a.z) > max(a.y, a.w);
+
+		vec4 blending_offset = vec4(0.0, a.y, 0.0, a.w);
+		vec2 blending_weight = a.yw;
+
+		SMAAMovc(bvec4(h, h, h, h), blending_offset, vec4(a.x, 0.0, a.z, 0.0));
+		SMAAMovc(bvec2(h, h), blending_weight, a.xz);
+		blending_weight /= dot(blending_weight, vec2(1.0, 1.0));
+
+		vec4 blending_coord = fma(blending_offset, vec4(params.inv_size.xy, -params.inv_size.xy), tex_coord.xyxy);
+
+		out_color.rgb = blending_weight.x * textureLinear(color_tex, blending_coord.xy);
+		out_color.rgb += blending_weight.y * textureLinear(color_tex, blending_coord.zw);
+		out_color.rgb = linear_to_srgb(out_color.rgb);
+		out_color.a = texture(color_tex, tex_coord).a;
+	}
+	if (bool(params.flags & FLAG_USE_8_BIT_DEBANDING)) {
+		// Divide by 255 to align to 8-bit quantization.
+		out_color.rgb += screen_space_dither(gl_FragCoord.xy, 255.0);
+	} else if (bool(params.flags & FLAG_USE_10_BIT_DEBANDING)) {
+		// Divide by 1023 to align to 10-bit quantization.
+		out_color.rgb += screen_space_dither(gl_FragCoord.xy, 1023.0);
+	}
+}