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593 lines
24 KiB
Metal
593 lines
24 KiB
Metal
//
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// ScanTarget.metal
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// Clock Signal
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//
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// Created by Thomas Harte on 04/08/2020.
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// Copyright © 2020 Thomas Harte. All rights reserved.
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//
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#include <metal_stdlib>
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using namespace metal;
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struct Uniforms {
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// This is used to scale scan positions, i.e. it provides the range
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// for mapping from scan-style integer positions into eye space.
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int2 scale;
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// Applies a multiplication to all cyclesSinceRetrace values.
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float cycleMultiplier;
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// This provides the intended height of a scan, in eye-coordinate terms.
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float lineWidth;
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// Provides zoom and offset to scale the source data.
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float3x3 sourceToDisplay;
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// Provides conversions to and from RGB for the active colour space.
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half3x3 toRGB;
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half3x3 fromRGB;
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// Describes the filter in use for chroma filtering; it'll be
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// 15 coefficients but they're symmetrical around the centre.
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half3 chromaKernel[8];
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// Describes the filter in use for luma filtering; 15 coefficients
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// symmetrical around the centre.
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half lumaKernel[8];
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// Sets the opacity at which output strips are drawn.
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half outputAlpha;
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// Sets the gamma power to which output colours are raised.
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half outputGamma;
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// Sets a brightness multiplier for output colours.
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half outputMultiplier;
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};
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namespace {
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constexpr sampler standardSampler( coord::pixel,
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address::clamp_to_edge, // Although arbitrary, stick with this address mode for compatibility all the way to MTLFeatureSet_iOS_GPUFamily1_v1.
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filter::nearest);
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constexpr sampler linearSampler( coord::pixel,
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address::clamp_to_edge, // Although arbitrary, stick with this address mode for compatibility all the way to MTLFeatureSet_iOS_GPUFamily1_v1.
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filter::linear);
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}
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// MARK: - Structs used for receiving data from the emulation.
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// This is intended to match the net effect of `Scan` as defined by the BufferingScanTarget,
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// with a couple of added fields.
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struct Scan {
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struct EndPoint {
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uint16_t position[2];
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uint16_t dataOffset;
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int16_t compositeAngle;
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uint16_t cyclesSinceRetrace;
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} endPoints[2];
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union {
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uint8_t compositeAmplitude;
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uint32_t padding; // TODO: reuse some padding as the next two fields, to save two bytes.
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};
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uint16_t dataY;
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uint16_t line;
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};
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// This matches the BufferingScanTarget's `Line`.
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struct Line {
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struct EndPoint {
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uint16_t position[2];
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int16_t compositeAngle;
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uint16_t cyclesSinceRetrace;
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} endPoints[2];
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uint8_t compositeAmplitude;
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uint16_t line;
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};
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// MARK: - Intermediate structs.
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struct SourceInterpolator {
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float4 position [[position]];
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float2 textureCoordinates;
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float unitColourPhase; // i.e. one unit per circle.
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float colourPhase; // i.e. 2*pi units per circle, just regular radians.
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half colourAmplitude [[flat]];
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};
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struct CopyInterpolator {
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float4 position [[position]];
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float2 textureCoordinates;
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};
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// MARK: - Vertex shaders.
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float2 textureLocation(constant Line *line, float offset, constant Uniforms &uniforms) {
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return float2(
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uniforms.cycleMultiplier * mix(line->endPoints[0].cyclesSinceRetrace, line->endPoints[1].cyclesSinceRetrace, offset),
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line->line + 0.5f);
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}
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float2 textureLocation(constant Scan *scan, float offset, constant Uniforms &) {
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return float2(
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mix(scan->endPoints[0].dataOffset, scan->endPoints[1].dataOffset, offset),
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scan->dataY + 0.5f);
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}
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template <typename Input> SourceInterpolator toDisplay(
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constant Uniforms &uniforms [[buffer(1)]],
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constant Input *inputs [[buffer(0)]],
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uint instanceID [[instance_id]],
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uint vertexID [[vertex_id]]) {
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SourceInterpolator output;
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// Get start and end vertices in regular float2 form.
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const float2 start = float2(
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float(inputs[instanceID].endPoints[0].position[0]) / float(uniforms.scale.x),
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float(inputs[instanceID].endPoints[0].position[1]) / float(uniforms.scale.y)
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);
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const float2 end = float2(
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float(inputs[instanceID].endPoints[1].position[0]) / float(uniforms.scale.x),
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float(inputs[instanceID].endPoints[1].position[1]) / float(uniforms.scale.y)
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);
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// Calculate the tangent and normal.
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const float2 tangent = (end - start);
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const float2 normal = float2(tangent.y, -tangent.x) / length(tangent);
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// Load up the colour details.
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output.colourAmplitude = float(inputs[instanceID].compositeAmplitude) / 255.0f;
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output.unitColourPhase = mix(
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float(inputs[instanceID].endPoints[0].compositeAngle),
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float(inputs[instanceID].endPoints[1].compositeAngle),
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float((vertexID&2) >> 1)
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) / 64.0f;
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output.colourPhase = 2.0f * 3.141592654f * output.unitColourPhase;
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// Hence determine this quad's real shape, using vertexID to pick a corner.
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// position2d is now in the range [0, 1].
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const float2 sourcePosition = start + (float(vertexID&2) * 0.5f) * tangent + (float(vertexID&1) - 0.5f) * normal * uniforms.lineWidth;
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const float2 position2d = (uniforms.sourceToDisplay * float3(sourcePosition, 1.0f)).xy;
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output.position = float4(
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position2d,
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0.0f,
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1.0f
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);
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output.textureCoordinates = textureLocation(&inputs[instanceID], float((vertexID&2) >> 1), uniforms);
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return output;
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}
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// These next two assume the incoming geometry to be a four-vertex triangle strip; each instance will therefore
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// produce a quad.
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vertex SourceInterpolator scanToDisplay( constant Uniforms &uniforms [[buffer(1)]],
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constant Scan *scans [[buffer(0)]],
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uint instanceID [[instance_id]],
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uint vertexID [[vertex_id]]) {
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return toDisplay(uniforms, scans, instanceID, vertexID);
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}
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vertex SourceInterpolator lineToDisplay( constant Uniforms &uniforms [[buffer(1)]],
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constant Line *lines [[buffer(0)]],
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uint instanceID [[instance_id]],
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uint vertexID [[vertex_id]]) {
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return toDisplay(uniforms, lines, instanceID, vertexID);
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}
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// This assumes that it needs to generate endpoints for a line segment.
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vertex SourceInterpolator scanToComposition( constant Uniforms &uniforms [[buffer(1)]],
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constant Scan *scans [[buffer(0)]],
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uint instanceID [[instance_id]],
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uint vertexID [[vertex_id]],
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texture2d<float> texture [[texture(0)]]) {
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SourceInterpolator result;
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// Populate result as if direct texture access were available.
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result.position.x = uniforms.cycleMultiplier * mix(scans[instanceID].endPoints[0].cyclesSinceRetrace, scans[instanceID].endPoints[1].cyclesSinceRetrace, float(vertexID));
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result.position.y = scans[instanceID].line;
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result.position.zw = float2(0.0f, 1.0f);
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result.textureCoordinates.x = mix(scans[instanceID].endPoints[0].dataOffset, scans[instanceID].endPoints[1].dataOffset, float(vertexID));
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result.textureCoordinates.y = scans[instanceID].dataY;
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result.unitColourPhase = mix(
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float(scans[instanceID].endPoints[0].compositeAngle),
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float(scans[instanceID].endPoints[1].compositeAngle),
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float(vertexID)
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) / 64.0f;
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result.colourPhase = 2.0f * 3.141592654f * result.unitColourPhase;
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result.colourAmplitude = float(scans[instanceID].compositeAmplitude) / 255.0f;
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// Map position into eye space, allowing for target texture dimensions.
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const float2 textureSize = float2(texture.get_width(), texture.get_height());
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result.position.xy =
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((result.position.xy + float2(0.0f, 0.5f)) / textureSize)
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* float2(2.0f, -2.0f) + float2(-1.0f, 1.0f);
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return result;
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}
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vertex CopyInterpolator copyVertex(uint vertexID [[vertex_id]], texture2d<float> texture [[texture(0)]]) {
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CopyInterpolator vert;
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const uint x = vertexID & 1;
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const uint y = (vertexID >> 1) & 1;
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vert.textureCoordinates = float2(
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x * texture.get_width(),
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y * texture.get_height()
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);
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vert.position = float4(
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float(x) * 2.0 - 1.0,
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1.0 - float(y) * 2.0,
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0.0,
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1.0
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);
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return vert;
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}
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// MARK: - Various input format conversion samplers.
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half2 quadrature(float phase) {
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return half2(cos(phase), sin(phase));
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}
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half4 composite(half level, half2 quadrature, half amplitude) {
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return half4(
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level,
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half2(0.5f) + quadrature*half(0.5f),
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amplitude
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);
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}
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// The luminance formats can be sampled either in their natural format, or to the intermediate
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// composite format used for composition. Direct sampling is always for final output, so the two
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// 8-bit formats also provide a gamma option.
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half convertLuminance1(SourceInterpolator vert [[stage_in]], texture2d<ushort> texture [[texture(0)]]) {
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return clamp(half(texture.sample(standardSampler, vert.textureCoordinates).r), half(0.0f), half(1.0f));
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}
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half convertLuminance8(SourceInterpolator vert [[stage_in]], texture2d<half> texture [[texture(0)]]) {
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return texture.sample(standardSampler, vert.textureCoordinates).r;
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}
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half convertPhaseLinkedLuminance8(SourceInterpolator vert [[stage_in]], texture2d<half> texture [[texture(0)]]) {
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const int offset = int(vert.unitColourPhase * 4.0f) & 3;
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auto sample = texture.sample(standardSampler, vert.textureCoordinates);
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return sample[offset];
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}
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#define CompositeSet(name, type) \
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fragment half4 sample##name(SourceInterpolator vert [[stage_in]], texture2d<type> texture [[texture(0)]], constant Uniforms &uniforms [[buffer(0)]]) { \
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const half luminance = convert##name(vert, texture) * uniforms.outputMultiplier; \
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return half4(half3(luminance), uniforms.outputAlpha); \
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} \
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\
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fragment half4 sample##name##WithGamma(SourceInterpolator vert [[stage_in]], texture2d<type> texture [[texture(0)]], constant Uniforms &uniforms [[buffer(0)]]) { \
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const half luminance = pow(convert##name(vert, texture) * uniforms.outputMultiplier, uniforms.outputGamma); \
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return half4(half3(luminance), uniforms.outputAlpha); \
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} \
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\
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fragment half4 compositeSample##name(SourceInterpolator vert [[stage_in]], texture2d<type> texture [[texture(0)]], constant Uniforms &uniforms [[buffer(0)]]) { \
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const half luminance = convert##name(vert, texture) * uniforms.outputMultiplier; \
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return composite(luminance, quadrature(vert.colourPhase), vert.colourAmplitude); \
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}
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CompositeSet(Luminance1, ushort);
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CompositeSet(Luminance8, half);
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CompositeSet(PhaseLinkedLuminance8, half);
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#undef CompositeSet
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// The luminance/phase format can produce either composite or S-Video.
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/// @returns A 2d vector comprised where .x = luminance; .y = chroma.
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half2 convertLuminance8Phase8(SourceInterpolator vert [[stage_in]], texture2d<half> texture [[texture(0)]]) {
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const auto luminancePhase = texture.sample(standardSampler, vert.textureCoordinates).rg;
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const half phaseOffset = 3.141592654 * 4.0 * luminancePhase.g;
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const half rawChroma = step(luminancePhase.g, half(0.75f)) * cos(vert.colourPhase + phaseOffset);
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return half2(luminancePhase.r, rawChroma);
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}
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fragment half4 compositeSampleLuminance8Phase8(SourceInterpolator vert [[stage_in]], texture2d<half> texture [[texture(0)]]) {
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const half2 luminanceChroma = convertLuminance8Phase8(vert, texture);
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const half luminance = mix(luminanceChroma.r, luminanceChroma.g, vert.colourAmplitude);
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return composite(luminance, quadrature(vert.colourPhase), vert.colourAmplitude);
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}
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fragment half4 sampleLuminance8Phase8(SourceInterpolator vert [[stage_in]], texture2d<half> texture [[texture(0)]]) {
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const half2 luminanceChroma = convertLuminance8Phase8(vert, texture);
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const half2 qam = quadrature(vert.colourPhase) * half(0.5f);
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return half4(luminanceChroma.r,
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half2(0.5f) + luminanceChroma.g*qam,
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half(1.0f));
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}
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fragment half4 directCompositeSampleLuminance8Phase8(SourceInterpolator vert [[stage_in]], texture2d<half> texture [[texture(0)]], constant Uniforms &uniforms [[buffer(0)]]) {
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const half2 luminanceChroma = convertLuminance8Phase8(vert, texture);
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const half luminance = mix(luminanceChroma.r * uniforms.outputMultiplier, luminanceChroma.g, vert.colourAmplitude);
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return half4(half3(luminance), uniforms.outputAlpha);
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}
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fragment half4 directCompositeSampleLuminance8Phase8WithGamma(SourceInterpolator vert [[stage_in]], texture2d<half> texture [[texture(0)]], constant Uniforms &uniforms [[buffer(0)]]) {
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const half2 luminanceChroma = convertLuminance8Phase8(vert, texture);
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const half luminance = mix(pow(luminanceChroma.r * uniforms.outputMultiplier, uniforms.outputGamma), luminanceChroma.g, vert.colourAmplitude);
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return half4(half3(luminance), uniforms.outputAlpha);
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}
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// All the RGB formats can produce RGB, composite or S-Video.
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half3 convertRed8Green8Blue8(SourceInterpolator vert, texture2d<half> texture) {
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return texture.sample(standardSampler, vert.textureCoordinates).rgb;
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}
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half3 convertRed4Green4Blue4(SourceInterpolator vert, texture2d<ushort> texture) {
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const auto sample = texture.sample(standardSampler, vert.textureCoordinates).rg;
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return half3(sample.r&15, (sample.g >> 4)&15, sample.g&15) / 15.0f;
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}
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half3 convertRed2Green2Blue2(SourceInterpolator vert, texture2d<ushort> texture) {
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const auto sample = texture.sample(standardSampler, vert.textureCoordinates).r;
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return half3((sample >> 4)&3, (sample >> 2)&3, sample&3) / 3.0f;
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}
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half3 convertRed1Green1Blue1(SourceInterpolator vert, texture2d<ushort> texture) {
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const auto sample = texture.sample(standardSampler, vert.textureCoordinates).r;
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return clamp(half3(sample&4, sample&2, sample&1), half(0.0f), half(1.0f));
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}
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#define DeclareShaders(name, pixelType) \
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fragment half4 sample##name(SourceInterpolator vert [[stage_in]], texture2d<pixelType> texture [[texture(0)]], constant Uniforms &uniforms [[buffer(0)]]) { \
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return half4(convert##name(vert, texture), uniforms.outputAlpha); \
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} \
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\
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fragment half4 sample##name##WithGamma(SourceInterpolator vert [[stage_in]], texture2d<pixelType> texture [[texture(0)]], constant Uniforms &uniforms [[buffer(0)]]) { \
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return half4(pow(convert##name(vert, texture), uniforms.outputGamma), uniforms.outputAlpha); \
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} \
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\
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fragment half4 svideoSample##name(SourceInterpolator vert [[stage_in]], texture2d<pixelType> texture [[texture(0)]], constant Uniforms &uniforms [[buffer(0)]]) { \
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const auto colour = uniforms.fromRGB * convert##name(vert, texture); \
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const half2 qam = quadrature(vert.colourPhase); \
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const half chroma = dot(colour.gb, qam); \
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return half4( \
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colour.r, \
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half2(0.5f) + chroma*qam*half(0.5f), \
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half(1.0f) \
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); \
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} \
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\
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half composite##name(SourceInterpolator vert, texture2d<pixelType> texture, constant Uniforms &uniforms, half2 colourSubcarrier) { \
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const auto colour = uniforms.fromRGB * convert##name(vert, texture); \
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return mix(colour.r, dot(colour.gb, colourSubcarrier), half(vert.colourAmplitude)); \
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} \
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\
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fragment half4 compositeSample##name(SourceInterpolator vert [[stage_in]], texture2d<pixelType> texture [[texture(0)]], constant Uniforms &uniforms [[buffer(0)]]) { \
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const half2 colourSubcarrier = quadrature(vert.colourPhase); \
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return composite(composite##name(vert, texture, uniforms, colourSubcarrier), colourSubcarrier, vert.colourAmplitude); \
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} \
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\
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fragment half4 directCompositeSample##name(SourceInterpolator vert [[stage_in]], texture2d<pixelType> texture [[texture(0)]], constant Uniforms &uniforms [[buffer(0)]]) { \
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const half level = composite##name(vert, texture, uniforms, quadrature(vert.colourPhase)); \
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return half4(half3(level), uniforms.outputAlpha); \
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} \
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\
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fragment half4 directCompositeSample##name##WithGamma(SourceInterpolator vert [[stage_in]], texture2d<pixelType> texture [[texture(0)]], constant Uniforms &uniforms [[buffer(0)]]) { \
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const half level = pow(composite##name(vert, texture, uniforms, quadrature(vert.colourPhase)), uniforms.outputGamma); \
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return half4(half3(level), uniforms.outputAlpha); \
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}
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DeclareShaders(Red8Green8Blue8, half)
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DeclareShaders(Red4Green4Blue4, ushort)
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DeclareShaders(Red2Green2Blue2, ushort)
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DeclareShaders(Red1Green1Blue1, ushort)
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fragment half4 copyFragment(CopyInterpolator vert [[stage_in]], texture2d<half> texture [[texture(0)]]) {
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return texture.sample(standardSampler, vert.textureCoordinates);
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}
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fragment half4 interpolateFragment(CopyInterpolator vert [[stage_in]], texture2d<half> texture [[texture(0)]]) {
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return texture.sample(linearSampler, vert.textureCoordinates);
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}
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fragment half4 clearFragment(constant Uniforms &uniforms [[buffer(0)]]) {
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return half4(0.0, 0.0, 0.0, uniforms.outputAlpha);
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}
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// MARK: - Compute kernels
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/// Given input pixels of the form (luminance, 0.5 + 0.5*chrominance*cos(phase), 0.5 + 0.5*chrominance*sin(phase)), applies a lowpass
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/// filter to the two chrominance parts, then uses the toRGB matrix to convert to RGB and stores.
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template <bool applyGamma> void filterChromaKernel( texture2d<half, access::read> inTexture [[texture(0)]],
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texture2d<half, access::write> outTexture [[texture(1)]],
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uint2 gid [[thread_position_in_grid]],
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constant Uniforms &uniforms [[buffer(0)]],
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constant int &offset [[buffer(1)]]) {
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constexpr half4 moveToZero(0.0f, 0.5f, 0.5f, 0.0f);
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const half4 rawSamples[] = {
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inTexture.read(gid + uint2(0, offset)) - moveToZero,
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inTexture.read(gid + uint2(1, offset)) - moveToZero,
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inTexture.read(gid + uint2(2, offset)) - moveToZero,
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inTexture.read(gid + uint2(3, offset)) - moveToZero,
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inTexture.read(gid + uint2(4, offset)) - moveToZero,
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inTexture.read(gid + uint2(5, offset)) - moveToZero,
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inTexture.read(gid + uint2(6, offset)) - moveToZero,
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inTexture.read(gid + uint2(7, offset)) - moveToZero,
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inTexture.read(gid + uint2(8, offset)) - moveToZero,
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inTexture.read(gid + uint2(9, offset)) - moveToZero,
|
|
inTexture.read(gid + uint2(10, offset)) - moveToZero,
|
|
inTexture.read(gid + uint2(11, offset)) - moveToZero,
|
|
inTexture.read(gid + uint2(12, offset)) - moveToZero,
|
|
inTexture.read(gid + uint2(13, offset)) - moveToZero,
|
|
inTexture.read(gid + uint2(14, offset)) - moveToZero,
|
|
};
|
|
|
|
#define Sample(x, y) uniforms.chromaKernel[y] * rawSamples[x].rgb
|
|
const half3 colour =
|
|
Sample(0, 0) + Sample(1, 1) + Sample(2, 2) + Sample(3, 3) + Sample(4, 4) + Sample(5, 5) + Sample(6, 6) +
|
|
Sample(7, 7) +
|
|
Sample(8, 6) + Sample(9, 5) + Sample(10, 4) + Sample(11, 3) + Sample(12, 2) + Sample(13, 1) + Sample(14, 0);
|
|
#undef Sample
|
|
|
|
const half4 output = half4(uniforms.toRGB * colour * uniforms.outputMultiplier, uniforms.outputAlpha);
|
|
if(applyGamma) {
|
|
outTexture.write(pow(output, uniforms.outputGamma), gid + uint2(7, offset));
|
|
} else {
|
|
outTexture.write(output, gid + uint2(7, offset));
|
|
}
|
|
}
|
|
|
|
kernel void filterChromaKernelNoGamma( texture2d<half, access::read> inTexture [[texture(0)]],
|
|
texture2d<half, access::write> outTexture [[texture(1)]],
|
|
uint2 gid [[thread_position_in_grid]],
|
|
constant Uniforms &uniforms [[buffer(0)]],
|
|
constant int &offset [[buffer(1)]]) {
|
|
filterChromaKernel<false>(inTexture, outTexture, gid, uniforms, offset);
|
|
}
|
|
|
|
kernel void filterChromaKernelWithGamma( texture2d<half, access::read> inTexture [[texture(0)]],
|
|
texture2d<half, access::write> outTexture [[texture(1)]],
|
|
uint2 gid [[thread_position_in_grid]],
|
|
constant Uniforms &uniforms [[buffer(0)]],
|
|
constant int &offset [[buffer(1)]]) {
|
|
filterChromaKernel<true>(inTexture, outTexture, gid, uniforms, offset);
|
|
}
|
|
|
|
void setSeparatedLumaChroma(half luminance, half4 centreSample, texture2d<half, access::write> outTexture, uint2 gid, int offset) {
|
|
// The mix/steps below ensures that the absence of a colour burst leads the colour subcarrier to be discarded.
|
|
const half isColour = step(half(0.01f), centreSample.a);
|
|
const half chroma = (centreSample.r - luminance) / mix(half(1.0f), centreSample.a, isColour);
|
|
outTexture.write(half4(
|
|
luminance / mix(half(1.0f), (half(1.0f) - centreSample.a), isColour),
|
|
isColour * (centreSample.gb - half2(0.5f)) * chroma + half2(0.5f),
|
|
1.0f
|
|
),
|
|
gid + uint2(7, offset));
|
|
}
|
|
|
|
|
|
/// Given input pixels of the form:
|
|
///
|
|
/// (composite sample, cos(phase), sin(phase), colour amplitude), applies a lowpass
|
|
///
|
|
/// Filters to separate luminance, subtracts that and scales and maps the remaining chrominance in order to output
|
|
/// pixels in the form:
|
|
///
|
|
/// (luminance, 0.5 + 0.5*chrominance*cos(phase), 0.5 + 0.5*chrominance*sin(phase))
|
|
///
|
|
/// i.e. the input form for the filterChromaKernel, above].
|
|
kernel void separateLumaKernel15( texture2d<half, access::read> inTexture [[texture(0)]],
|
|
texture2d<half, access::write> outTexture [[texture(1)]],
|
|
uint2 gid [[thread_position_in_grid]],
|
|
constant Uniforms &uniforms [[buffer(0)]],
|
|
constant int &offset [[buffer(1)]]) {
|
|
const half4 centreSample = inTexture.read(gid + uint2(7, offset));
|
|
const half rawSamples[] = {
|
|
inTexture.read(gid + uint2(0, offset)).r, inTexture.read(gid + uint2(1, offset)).r,
|
|
inTexture.read(gid + uint2(2, offset)).r, inTexture.read(gid + uint2(3, offset)).r,
|
|
inTexture.read(gid + uint2(4, offset)).r, inTexture.read(gid + uint2(5, offset)).r,
|
|
inTexture.read(gid + uint2(6, offset)).r,
|
|
centreSample.r,
|
|
inTexture.read(gid + uint2(8, offset)).r,
|
|
inTexture.read(gid + uint2(9, offset)).r, inTexture.read(gid + uint2(10, offset)).r,
|
|
inTexture.read(gid + uint2(11, offset)).r, inTexture.read(gid + uint2(12, offset)).r,
|
|
inTexture.read(gid + uint2(13, offset)).r, inTexture.read(gid + uint2(14, offset)).r,
|
|
};
|
|
|
|
#define Sample(x, y) uniforms.lumaKernel[y] * rawSamples[x]
|
|
const half luminance =
|
|
Sample(0, 0) + Sample(1, 1) + Sample(2, 2) + Sample(3, 3) + Sample(4, 4) + Sample(5, 5) + Sample(6, 6) +
|
|
Sample(7, 7) +
|
|
Sample(8, 6) + Sample(9, 5) + Sample(10, 4) + Sample(11, 3) + Sample(12, 2) + Sample(13, 1) + Sample(14, 0);
|
|
#undef Sample
|
|
|
|
return setSeparatedLumaChroma(luminance, centreSample, outTexture, gid, offset);
|
|
}
|
|
|
|
kernel void separateLumaKernel9( texture2d<half, access::read> inTexture [[texture(0)]],
|
|
texture2d<half, access::write> outTexture [[texture(1)]],
|
|
uint2 gid [[thread_position_in_grid]],
|
|
constant Uniforms &uniforms [[buffer(0)]],
|
|
constant int &offset [[buffer(1)]]) {
|
|
const half4 centreSample = inTexture.read(gid + uint2(7, offset));
|
|
const half rawSamples[] = {
|
|
inTexture.read(gid + uint2(3, offset)).r, inTexture.read(gid + uint2(4, offset)).r,
|
|
inTexture.read(gid + uint2(5, offset)).r, inTexture.read(gid + uint2(6, offset)).r,
|
|
centreSample.r,
|
|
inTexture.read(gid + uint2(8, offset)).r, inTexture.read(gid + uint2(9, offset)).r,
|
|
inTexture.read(gid + uint2(10, offset)).r, inTexture.read(gid + uint2(11, offset)).r
|
|
};
|
|
|
|
#define Sample(x, y) uniforms.lumaKernel[y] * rawSamples[x]
|
|
const half luminance =
|
|
Sample(0, 3) + Sample(1, 4) + Sample(2, 5) + Sample(3, 6) +
|
|
Sample(4, 7) +
|
|
Sample(5, 6) + Sample(6, 5) + Sample(7, 4) + Sample(8, 3);
|
|
#undef Sample
|
|
|
|
return setSeparatedLumaChroma(luminance, centreSample, outTexture, gid, offset);
|
|
}
|
|
|
|
kernel void separateLumaKernel7( texture2d<half, access::read> inTexture [[texture(0)]],
|
|
texture2d<half, access::write> outTexture [[texture(1)]],
|
|
uint2 gid [[thread_position_in_grid]],
|
|
constant Uniforms &uniforms [[buffer(0)]],
|
|
constant int &offset [[buffer(1)]]) {
|
|
const half4 centreSample = inTexture.read(gid + uint2(7, offset));
|
|
const half rawSamples[] = {
|
|
inTexture.read(gid + uint2(4, offset)).r,
|
|
inTexture.read(gid + uint2(5, offset)).r, inTexture.read(gid + uint2(6, offset)).r,
|
|
centreSample.r,
|
|
inTexture.read(gid + uint2(8, offset)).r, inTexture.read(gid + uint2(9, offset)).r,
|
|
inTexture.read(gid + uint2(10, offset)).r
|
|
};
|
|
|
|
#define Sample(x, y) uniforms.lumaKernel[y] * rawSamples[x]
|
|
const half luminance =
|
|
Sample(0, 4) + Sample(1, 5) + Sample(2, 6) +
|
|
Sample(3, 7) +
|
|
Sample(4, 6) + Sample(5, 5) + Sample(6, 4);
|
|
#undef Sample
|
|
|
|
return setSeparatedLumaChroma(luminance, centreSample, outTexture, gid, offset);
|
|
}
|
|
|
|
kernel void separateLumaKernel5( texture2d<half, access::read> inTexture [[texture(0)]],
|
|
texture2d<half, access::write> outTexture [[texture(1)]],
|
|
uint2 gid [[thread_position_in_grid]],
|
|
constant Uniforms &uniforms [[buffer(0)]],
|
|
constant int &offset [[buffer(1)]]) {
|
|
const half4 centreSample = inTexture.read(gid + uint2(7, offset));
|
|
const half rawSamples[] = {
|
|
inTexture.read(gid + uint2(5, offset)).r, inTexture.read(gid + uint2(6, offset)).r,
|
|
centreSample.r,
|
|
inTexture.read(gid + uint2(8, offset)).r, inTexture.read(gid + uint2(9, offset)).r,
|
|
};
|
|
|
|
#define Sample(x, y) uniforms.lumaKernel[y] * rawSamples[x]
|
|
const half luminance =
|
|
Sample(0, 5) + Sample(1, 6) +
|
|
Sample(2, 7) +
|
|
Sample(3, 6) + Sample(4, 5);
|
|
#undef Sample
|
|
|
|
return setSeparatedLumaChroma(luminance, centreSample, outTexture, gid, offset);
|
|
}
|
|
|
|
kernel void clearKernel( texture2d<half, access::write> outTexture [[texture(0)]],
|
|
uint2 gid [[thread_position_in_grid]]) {
|
|
outTexture.write(half4(0.0f, 0.0f, 0.0f, 1.0f), gid);
|
|
}
|