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CLK/Outputs/OpenGL/ScanTargetGLSLFragments.cpp
2018-11-24 22:39:53 -05:00

434 lines
16 KiB
C++

//
// ScanTargetVertexArrayAttributs.cpp
// Clock Signal
//
// Created by Thomas Harte on 11/11/2018.
// Copyright © 2018 Thomas Harte. All rights reserved.
//
#include "ScanTarget.hpp"
#include "../../SignalProcessing/FIRFilter.hpp"
using namespace Outputs::Display::OpenGL;
std::string ScanTarget::glsl_globals(ShaderType type) {
switch(type) {
case ShaderType::InputScan:
case ShaderType::ProcessedScan:
return
"#version 150\n"
"uniform vec2 scale;"
"uniform mat3 lumaChromaToRGB;"
"uniform mat3 rgbToLumaChroma;"
"uniform float rowHeight;"
"uniform float processingWidth;"
"in vec2 startPoint;"
"in float startDataX;"
"in float startCompositeAngle;"
"in vec2 endPoint;"
"in float endDataX;"
"in float endCompositeAngle;"
"in float dataY;"
"in float lineY;"
"in float compositeAmplitude;";
case ShaderType::Line:
return
"#version 150\n"
"uniform vec2 scale;"
"uniform float rowHeight;"
"uniform float processingWidth;"
"in vec2 startPoint;"
"in vec2 endPoint;"
"in float lineY;"
"uniform sampler2D textureName;"
"uniform vec2 origin;"
"uniform vec2 size;";
}
}
std::vector<Shader::AttributeBinding> ScanTarget::attribute_bindings(ShaderType type) {
switch(type) {
case ShaderType::InputScan:
case ShaderType::ProcessedScan:
return {
{"startPoint", 0},
{"startDataX", 1},
{"startCompositeAngle", 2},
{"endPoint", 3},
{"endDataX", 4},
{"endCompositeAngle", 5},
{"dataY", 6},
{"lineY", 7},
{"compositeAmplitude", 8},
};
case ShaderType::Line:
return {
{"startPoint", 0},
{"endPoint", 1},
{"lineY", 2},
};
}
}
std::string ScanTarget::glsl_default_vertex_shader(ShaderType type) {
switch(type) {
case ShaderType::InputScan:
case ShaderType::ProcessedScan: {
std::string result;
if(type == ShaderType::InputScan) {
result +=
"out vec2 textureCoordinate;"
"uniform usampler2D textureName;";
} else {
result +=
"out vec2 textureCoordinates[11];"
"uniform sampler2D textureName;";
}
result +=
"out float compositeAngle;"
"out float oneOverCompositeAmplitude;"
"void main(void) {"
"float lateral = float(gl_VertexID & 1);"
"float longitudinal = float((gl_VertexID & 2) >> 1);"
"compositeAngle = (mix(startCompositeAngle, endCompositeAngle, lateral) / 32.0) * 3.141592654;"
"oneOverCompositeAmplitude = mix(0.0, 255.0 / compositeAmplitude, step(0.01, compositeAmplitude));";
if(type == ShaderType::InputScan) {
result +=
"textureCoordinate = vec2(mix(startDataX, endDataX, lateral), dataY + 0.5) / textureSize(textureName, 0);"
"vec2 eyePosition = vec2(mix(startPoint.x, endPoint.x, lateral) * processingWidth, lineY + longitudinal) / vec2(scale.x, 2048.0);";
} else {
result +=
"vec2 sourcePosition = vec2(mix(startPoint.x, endPoint.x, lateral) * processingWidth, lineY + 0.5);"
"vec2 eyePosition = (sourcePosition + vec2(0.0, longitudinal - 0.5)) / vec2(scale.x, 2048.0);"
"sourcePosition /= vec2(scale.x, 2048.0);"
"textureCoordinates[0] = sourcePosition + vec2(-5.0, 0.0) / textureSize(textureName, 0);"
"textureCoordinates[1] = sourcePosition + vec2(-4.0, 0.0) / textureSize(textureName, 0);"
"textureCoordinates[2] = sourcePosition + vec2(-3.0, 0.0) / textureSize(textureName, 0);"
"textureCoordinates[3] = sourcePosition + vec2(-2.0, 0.0) / textureSize(textureName, 0);"
"textureCoordinates[4] = sourcePosition + vec2(-1.0, 0.0) / textureSize(textureName, 0);"
"textureCoordinates[5] = sourcePosition;"
"textureCoordinates[6] = sourcePosition + vec2(1.0, 0.0) / textureSize(textureName, 0);"
"textureCoordinates[7] = sourcePosition + vec2(2.0, 0.0) / textureSize(textureName, 0);"
"textureCoordinates[8] = sourcePosition + vec2(3.0, 0.0) / textureSize(textureName, 0);"
"textureCoordinates[9] = sourcePosition + vec2(4.0, 0.0) / textureSize(textureName, 0);"
"textureCoordinates[10] = sourcePosition + vec2(5.0, 0.0) / textureSize(textureName, 0);"
"eyePosition = eyePosition;";
}
return result +
"gl_Position = vec4(eyePosition*2.0 - vec2(1.0), 0.0, 1.0);"
"}";
}
case ShaderType::Line:
return
"out vec2 textureCoordinate;"
"void main(void) {"
"float lateral = float(gl_VertexID & 1);"
"float longitudinal = float((gl_VertexID & 2) >> 1);"
"textureCoordinate = vec2(lateral * processingWidth, lineY + 0.5) / vec2(1.0, textureSize(textureName, 0).y);"
"vec2 centrePoint = mix(startPoint, endPoint, lateral) / scale;"
"vec2 height = normalize(endPoint - startPoint).yx * (longitudinal - 0.5) * rowHeight;"
"vec2 eyePosition = vec2(-1.0, 1.0) + vec2(2.0, -2.0) * (((centrePoint + height) - origin) / size);"
"gl_Position = vec4(eyePosition, 0.0, 1.0);"
"}";
}
}
void ScanTarget::enable_vertex_attributes(ShaderType type, Shader &target) {
switch(type) {
case ShaderType::InputScan:
case ShaderType::ProcessedScan:
for(int c = 0; c < 2; ++c) {
const std::string prefix = c ? "end" : "start";
target.enable_vertex_attribute_with_pointer(
prefix + "Point",
2, GL_UNSIGNED_SHORT, GL_FALSE,
sizeof(Scan),
reinterpret_cast<void *>(offsetof(Scan, scan.end_points[c].x)),
1);
target.enable_vertex_attribute_with_pointer(
prefix + "DataX",
1, GL_UNSIGNED_SHORT, GL_FALSE,
sizeof(Scan),
reinterpret_cast<void *>(offsetof(Scan, scan.end_points[c].data_offset)),
1);
target.enable_vertex_attribute_with_pointer(
prefix + "CompositeAngle",
1, GL_UNSIGNED_SHORT, GL_FALSE,
sizeof(Scan),
reinterpret_cast<void *>(offsetof(Scan, scan.end_points[c].composite_angle)),
1);
}
target.enable_vertex_attribute_with_pointer(
"dataY",
1, GL_UNSIGNED_SHORT, GL_FALSE,
sizeof(Scan),
reinterpret_cast<void *>(offsetof(Scan, data_y)),
1);
target.enable_vertex_attribute_with_pointer(
"lineY",
1, GL_UNSIGNED_SHORT, GL_FALSE,
sizeof(Scan),
reinterpret_cast<void *>(offsetof(Scan, line)),
1);
target.enable_vertex_attribute_with_pointer(
"compositeAmplitude",
1, GL_UNSIGNED_BYTE, GL_FALSE,
sizeof(Scan),
reinterpret_cast<void *>(offsetof(Scan, scan.composite_amplitude)),
1);
break;
case ShaderType::Line:
for(int c = 0; c < 2; ++c) {
const std::string prefix = c ? "end" : "start";
target.enable_vertex_attribute_with_pointer(
prefix + "Point",
2, GL_UNSIGNED_SHORT, GL_FALSE,
sizeof(Line),
reinterpret_cast<void *>(offsetof(Line, end_points[c].x)),
1);
}
target.enable_vertex_attribute_with_pointer(
"lineY",
1, GL_UNSIGNED_SHORT, GL_FALSE,
sizeof(Line),
reinterpret_cast<void *>(offsetof(Line, line)),
1);
break;
}
}
std::unique_ptr<Shader> ScanTarget::input_shader(InputDataType input_data_type, DisplayType display_type) {
std::string fragment_shader =
"#version 150\n"
"out vec3 fragColour;"
"in vec2 textureCoordinate;"
"in float compositeAngle;"
"in float oneOverCompositeAmplitude;"
"uniform mat3 lumaChromaToRGB;"
"uniform mat3 rgbToLumaChroma;"
"uniform usampler2D textureName;"
"void main(void) {";
DisplayType computed_display_type;
switch(input_data_type) {
case InputDataType::Luminance1:
computed_display_type = DisplayType::CompositeMonochrome;
fragment_shader += "fragColour = texture(textureName, textureCoordinate).rrr;";
if(computed_display_type != display_type) {
fragment_shader += "fragColour = clamp(fragColour, 0.0, 1.0);";
}
break;
case InputDataType::Luminance8:
computed_display_type = DisplayType::CompositeMonochrome;
fragment_shader += "fragColour = vec3(texture(textureName, textureCoordinate).r / 255.0);";
break;
case InputDataType::Luminance8Phase8:
computed_display_type = DisplayType::SVideo;
fragment_shader +=
"vec2 yc = texture(textureName, textureCoordinate).rg / vec2(255.0);"
"float phaseOffset = 3.141592654 * 2.0 * 2.0 * yc.y;"
"float rawChroma = step(yc.y, 0.75) * cos(compositeAngle + phaseOffset);"
"fragColour = vec3(yc.x, 0.5 + rawChroma*0.5, 0.0);";
break;
case InputDataType::Red1Green1Blue1:
computed_display_type = DisplayType::RGB;
fragment_shader +=
"uint textureValue = texture(textureName, textureCoordinate).r;"
"fragColour = uvec3(textureValue) & uvec3(4u, 2u, 1u);";
if(computed_display_type != display_type) {
fragment_shader += "fragColour = clamp(fragColour, 0.0, 1.0);";
}
break;
case InputDataType::Red2Green2Blue2:
computed_display_type = DisplayType::RGB;
fragment_shader +=
"uint textureValue = texture(textureName, textureCoordinate).r;"
"fragColour = vec3(float((textureValue >> 4) & 3u), float((textureValue >> 2) & 3u), float(textureValue & 3u)) / 3.0;";
break;
case InputDataType::Red4Green4Blue4:
computed_display_type = DisplayType::RGB;
fragment_shader +=
"uvec2 textureValue = texture(textureName, textureCoordinate).rg;"
"fragColour = vec3(float(textureValue.r) / 15.0, float(textureValue.g & 240u) / 240.0, float(textureValue.g & 15u) / 15.0);";
break;
case InputDataType::Red8Green8Blue8:
computed_display_type = DisplayType::RGB;
fragment_shader += "fragColour = texture(textureName, textureCoordinate).rgb / vec3(255.0);";
break;
}
// If the input type is RGB but the output type isn't then
// there'll definitely be an RGB to SVideo step.
if(computed_display_type == DisplayType::RGB && display_type != DisplayType::RGB) {
fragment_shader +=
"vec3 composite_colour = rgbToLumaChroma * fragColour;"
"vec2 quadrature = vec2(cos(compositeAngle), sin(compositeAngle));"
"fragColour = vec3(composite_colour.r, 0.5 + dot(quadrature, composite_colour.gb)*0.5, 0.0);";
}
// If the output type is SVideo, throw in an attempt to separate the two chrominance
// channels here.
if(display_type == DisplayType::SVideo) {
if(computed_display_type != DisplayType::RGB) {
fragment_shader +=
"vec2 quadrature = vec2(cos(compositeAngle), sin(compositeAngle));";
}
fragment_shader +=
"vec2 chroma = (((fragColour.y - 0.5)*2.0) * quadrature)*0.5 + vec2(0.5);"
"fragColour = vec3(fragColour.x, chroma);";
}
// Add an SVideo to composite step if necessary.
if(
(display_type == DisplayType::CompositeMonochrome || display_type == DisplayType::CompositeColour) &&
computed_display_type != DisplayType::CompositeMonochrome
) {
fragment_shader += "fragColour = vec3(mix(fragColour.r, 2.0*(fragColour.g - 0.5), 1.0 / oneOverCompositeAmplitude));";
}
return std::unique_ptr<Shader>(new Shader(
glsl_globals(ShaderType::InputScan) + glsl_default_vertex_shader(ShaderType::InputScan),
fragment_shader + "}",
attribute_bindings(ShaderType::InputScan)
));
}
std::vector<float> ScanTarget::coefficients_for_filter(int colour_cycle_numerator, int colour_cycle_denominator, int processing_width, float multiple_of_colour_clock) {
const float cycles_per_expanded_line = (float(colour_cycle_numerator) / float(colour_cycle_denominator)) / (float(processing_width) / float(LineBufferWidth));
const SignalProcessing::FIRFilter filter(11, float(LineBufferWidth), 0.0f, cycles_per_expanded_line * multiple_of_colour_clock);
return filter.get_coefficients();
}
std::unique_ptr<Shader> ScanTarget::svideo_to_rgb_shader(int colour_cycle_numerator, int colour_cycle_denominator, int processing_width) {
/*
Composite to S-Video conversion is achieved by filtering the input signal to obtain luminance, and then subtracting that
from the original to get chrominance.
(Colour cycle numerator)/(Colour cycle denominator) gives the number of colour cycles in (processing_width / LineBufferWidth),
there'll be at least four samples per colour clock and in practice at most just a shade more than 9.
*/
auto coefficients = coefficients_for_filter(colour_cycle_numerator, colour_cycle_denominator, processing_width, 0.25f);
auto shader = std::unique_ptr<Shader>(new Shader(
glsl_globals(ShaderType::ProcessedScan) + glsl_default_vertex_shader(ShaderType::ProcessedScan),
"#version 150\n"
"in vec2 textureCoordinates[11];"
"uniform vec4 textureWeights[3];"
"uniform sampler2D textureName;"
"uniform mat3 lumaChromaToRGB;"
"out vec3 fragColour;"
"void main() {"
"vec3 samples[11] = vec3[11]("
"texture(textureName, textureCoordinates[0]).rgb,"
"texture(textureName, textureCoordinates[1]).rgb,"
"texture(textureName, textureCoordinates[2]).rgb,"
"texture(textureName, textureCoordinates[3]).rgb,"
"texture(textureName, textureCoordinates[4]).rgb,"
"texture(textureName, textureCoordinates[5]).rgb,"
"texture(textureName, textureCoordinates[6]).rgb,"
"texture(textureName, textureCoordinates[7]).rgb,"
"texture(textureName, textureCoordinates[8]).rgb,"
"texture(textureName, textureCoordinates[9]).rgb,"
"texture(textureName, textureCoordinates[10]).rgb"
");"
"vec4 samples1[3] = vec4[3]("
"vec4(samples[0].g, samples[1].g, samples[2].g, samples[3].g),"
"vec4(samples[4].g, samples[5].g, samples[6].g, samples[7].g),"
"vec4(samples[8].g, samples[9].g, samples[10].g, 0.0)"
");"
"vec4 samples2[3] = vec4[3]("
"vec4(samples[0].b, samples[1].b, samples[2].b, samples[3].b),"
"vec4(samples[4].b, samples[5].b, samples[6].b, samples[7].b),"
"vec4(samples[8].b, samples[9].b, samples[10].b, 0.0)"
");"
"float channel1 = dot(textureWeights[0], samples1[0]) + dot(textureWeights[1], samples1[1]) + dot(textureWeights[2], samples1[2]);"
"float channel2 = dot(textureWeights[0], samples2[0]) + dot(textureWeights[1], samples2[1]) + dot(textureWeights[2], samples2[2]);"
"vec2 chroma = vec2(channel1, channel2)*2.0 - vec2(1.0);"
"fragColour = lumaChromaToRGB * vec3(samples[5].x, chroma);"
"}",
attribute_bindings(ShaderType::ProcessedScan)
));
coefficients.push_back(0.0f);
shader->set_uniform("textureWeights", 4, 3, coefficients.data());
return shader;
}
std::unique_ptr<Shader> ScanTarget::composite_to_svideo_shader(int colour_cycle_numerator, int colour_cycle_denominator, int processing_width) {
auto coefficients = coefficients_for_filter(colour_cycle_numerator, colour_cycle_denominator, processing_width, 0.5f);
auto shader = std::unique_ptr<Shader>(new Shader(
glsl_globals(ShaderType::ProcessedScan) + glsl_default_vertex_shader(ShaderType::ProcessedScan),
"#version 150\n"
"in vec2 textureCoordinates[11];"
"in float compositeAngle;"
"in float oneOverCompositeAmplitude;"
"uniform vec4 textureWeights[3];"
"uniform sampler2D textureName;"
"out vec3 fragColour;"
"void main() {"
"vec4 samples[3] = vec4[3]("
"vec4(texture(textureName, textureCoordinates[0]).r, texture(textureName, textureCoordinates[1]).r, texture(textureName, textureCoordinates[2]).r, texture(textureName, textureCoordinates[3]).r),"
"vec4(texture(textureName, textureCoordinates[4]).r, texture(textureName, textureCoordinates[5]).r, texture(textureName, textureCoordinates[6]).r, texture(textureName, textureCoordinates[7]).r),"
"vec4(texture(textureName, textureCoordinates[8]).r, texture(textureName, textureCoordinates[9]).r, texture(textureName, textureCoordinates[10]).r, 0.0)"
");"
"float luma = dot(textureWeights[0], samples[0]) + dot(textureWeights[1], samples[1]) + dot(textureWeights[2], samples[2]);"
"vec2 quadrature = vec2(cos(compositeAngle), sin(compositeAngle));"
"vec2 chroma = ((samples[1].y - luma) * oneOverCompositeAmplitude)*quadrature;"
"fragColour = vec3(luma, chroma*0.5 + vec2(0.5));"
"}",
attribute_bindings(ShaderType::ProcessedScan)
));
coefficients.push_back(0.0f);
shader->set_uniform("textureWeights", 4, 3, coefficients.data());
return shader;
}