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CLK/Outputs/CRT/Internals/CRTOpenGL.cpp

517 lines
19 KiB
C++

// CRTOpenGL.cpp
// Clock Signal
//
// Created by Thomas Harte on 03/02/2016.
// Copyright © 2016 Thomas Harte. All rights reserved.
//
#include "CRT.hpp"
#include <stdlib.h>
#include <math.h>
#include "CRTOpenGL.hpp"
#include "../../../SignalProcessing/FIRFilter.hpp"
#include "Shaders/OutputShader.hpp"
static const GLint internalFormatForDepth(size_t depth)
{
switch(depth)
{
default: return GL_FALSE;
case 1: return GL_R8UI;
case 2: return GL_RG8UI;
case 3: return GL_RGB8UI;
case 4: return GL_RGBA8UI;
}
}
static const GLenum formatForDepth(size_t depth)
{
switch(depth)
{
default: return GL_FALSE;
case 1: return GL_RED_INTEGER;
case 2: return GL_RG_INTEGER;
case 3: return GL_RGB_INTEGER;
case 4: return GL_RGBA_INTEGER;
}
}
struct Range {
GLsizei location, length;
};
static int getCircularRanges(GLsizei *start_pointer, GLsizei *end_pointer, GLsizei buffer_length, GLsizei granularity, Range *ranges)
{
GLsizei start = *start_pointer;
GLsizei end = *end_pointer;
*end_pointer %= buffer_length;
*start_pointer = *end_pointer;
start -= start%granularity;
end -= end%granularity;
GLsizei length = end - start;
if(!length) return 0;
if(length >= buffer_length)
{
ranges[0].location = 0;
ranges[0].length = buffer_length;
return 1;
}
else
{
ranges[0].location = start % buffer_length;
if(ranges[0].location + length <= buffer_length)
{
ranges[0].length = length;
return 1;
}
else
{
ranges[0].length = buffer_length - ranges[0].location;
ranges[1].location = 0;
ranges[1].length = length - ranges[0].length;
return 2;
}
}
}
static inline void drawArrayRanges(GLenum mode, GLsizei vertex_size, int number_of_ranges, Range *ranges)
{
for(int c = 0; c < number_of_ranges; c++)
{
glDrawArrays(mode, ranges[c].location / vertex_size, ranges[c].length / vertex_size);
}
}
static void submitArrayData(GLuint buffer, uint8_t *source, int number_of_ranges, Range *ranges)
{
glBindBuffer(GL_ARRAY_BUFFER, buffer);
for(int c = 0; c < number_of_ranges; c++)
{
uint8_t *data = (uint8_t *)glMapBufferRange(GL_ARRAY_BUFFER, ranges[c].location, ranges[c].length, GL_MAP_WRITE_BIT | GL_MAP_UNSYNCHRONIZED_BIT | GL_MAP_FLUSH_EXPLICIT_BIT);
memcpy(data, &source[ranges[c].location], (size_t)ranges[c].length);
glFlushMappedBufferRange(GL_ARRAY_BUFFER, ranges[c].location, ranges[c].length);
glUnmapBuffer(GL_ARRAY_BUFFER);
}
}
using namespace Outputs::CRT;
namespace {
static const GLenum composite_texture_unit = GL_TEXTURE0;
static const GLenum separated_texture_unit = GL_TEXTURE1;
static const GLenum filtered_y_texture_unit = GL_TEXTURE2;
static const GLenum filtered_texture_unit = GL_TEXTURE3;
static const GLenum source_data_texture_unit = GL_TEXTURE4;
static const GLenum pixel_accumulation_texture_unit = GL_TEXTURE5;
}
OpenGLOutputBuilder::OpenGLOutputBuilder(unsigned int buffer_depth) :
_output_mutex(new std::mutex),
_visible_area(Rect(0, 0, 1, 1)),
_composite_src_output_y(0),
_cleared_composite_output_y(0),
_composite_shader(nullptr),
_rgb_shader(nullptr),
_output_buffer_data(new uint8_t[OutputVertexBufferDataSize]),
_source_buffer_data(new uint8_t[SourceVertexBufferDataSize]),
_output_buffer_data_pointer(0),
_drawn_output_buffer_data_pointer(0),
_source_buffer_data_pointer(0),
_drawn_source_buffer_data_pointer(0),
_last_output_width(0),
_last_output_height(0),
_fence(nullptr)
{
_buffer_builder = std::unique_ptr<CRTInputBufferBuilder>(new CRTInputBufferBuilder(buffer_depth));
glBlendFunc(GL_SRC_ALPHA, GL_CONSTANT_COLOR);
glBlendColor(0.6f, 0.6f, 0.6f, 1.0f);
// Create intermediate textures and bind to slots 0, 1 and 2
compositeTexture = std::unique_ptr<OpenGL::TextureTarget>(new OpenGL::TextureTarget(IntermediateBufferWidth, IntermediateBufferHeight, composite_texture_unit));
separatedTexture = std::unique_ptr<OpenGL::TextureTarget>(new OpenGL::TextureTarget(IntermediateBufferWidth, IntermediateBufferHeight, separated_texture_unit));
filteredYTexture = std::unique_ptr<OpenGL::TextureTarget>(new OpenGL::TextureTarget(IntermediateBufferWidth, IntermediateBufferHeight, filtered_y_texture_unit));
filteredTexture = std::unique_ptr<OpenGL::TextureTarget>(new OpenGL::TextureTarget(IntermediateBufferWidth, IntermediateBufferHeight, filtered_texture_unit));
// create the surce texture
glGenTextures(1, &textureName);
glActiveTexture(source_data_texture_unit);
glBindTexture(GL_TEXTURE_2D, textureName);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexImage2D(GL_TEXTURE_2D, 0, internalFormatForDepth(_buffer_builder->get_bytes_per_pixel()), InputBufferBuilderWidth, InputBufferBuilderHeight, 0, formatForDepth(_buffer_builder->get_bytes_per_pixel()), GL_UNSIGNED_BYTE, nullptr);
// create the output vertex array
glGenVertexArrays(1, &output_vertex_array);
// create a buffer for output vertex attributes
glGenBuffers(1, &output_array_buffer);
glBindBuffer(GL_ARRAY_BUFFER, output_array_buffer);
glBufferData(GL_ARRAY_BUFFER, OutputVertexBufferDataSize, NULL, GL_STREAM_DRAW);
// create the source vertex array
glGenVertexArrays(1, &source_vertex_array);
// create a buffer for source vertex attributes
glGenBuffers(1, &source_array_buffer);
glBindBuffer(GL_ARRAY_BUFFER, source_array_buffer);
glBufferData(GL_ARRAY_BUFFER, SourceVertexBufferDataSize, NULL, GL_STREAM_DRAW);
}
OpenGLOutputBuilder::~OpenGLOutputBuilder()
{
glDeleteTextures(1, &textureName);
glDeleteBuffers(1, &output_array_buffer);
glDeleteBuffers(1, &source_array_buffer);
glDeleteVertexArrays(1, &output_vertex_array);
free(_composite_shader);
free(_rgb_shader);
}
void OpenGLOutputBuilder::draw_frame(unsigned int output_width, unsigned int output_height, bool only_if_dirty)
{
// lock down any further work on the current frame
_output_mutex->lock();
// establish essentials
if(!output_shader_program)
{
prepare_composite_input_shaders();
prepare_rgb_input_shaders();
prepare_source_vertex_array();
prepare_output_shader();
prepare_output_vertex_array();
set_timing_uniforms();
set_colour_space_uniforms();
}
// determine how many lines are newly reclaimed; they'll need to be cleared
Range clearing_zones[2], source_drawing_zones[2];
Range output_drawing_zones[2];
int number_of_clearing_zones = getCircularRanges(&_cleared_composite_output_y, &_composite_src_output_y, IntermediateBufferHeight, 1, clearing_zones);
int number_of_source_drawing_zones = getCircularRanges(&_drawn_source_buffer_data_pointer, &_source_buffer_data_pointer, SourceVertexBufferDataSize, 2*SourceVertexSize, source_drawing_zones);
int number_of_output_drawing_zones = getCircularRanges(&_drawn_output_buffer_data_pointer, &_output_buffer_data_pointer, OutputVertexBufferDataSize, 6*OutputVertexSize, output_drawing_zones);
uint16_t completed_texture_y = _buffer_builder->get_and_finalise_current_line();
if(_fence != nullptr)
{
glClientWaitSync(_fence, GL_SYNC_FLUSH_COMMANDS_BIT, GL_TIMEOUT_IGNORED);
glDeleteSync(_fence);
}
// release the mapping, giving up on trying to draw if data has been lost
submitArrayData(output_array_buffer, _output_buffer_data.get(), number_of_output_drawing_zones, output_drawing_zones);
// bind and flush the source array buffer
submitArrayData(source_array_buffer, _source_buffer_data.get(), number_of_source_drawing_zones, source_drawing_zones);
// make sure there's a target to draw to
if(!framebuffer || framebuffer->get_height() != output_height || framebuffer->get_width() != output_width)
{
std::unique_ptr<OpenGL::TextureTarget> new_framebuffer = std::unique_ptr<OpenGL::TextureTarget>(new OpenGL::TextureTarget((GLsizei)output_width, (GLsizei)output_height, pixel_accumulation_texture_unit));
if(framebuffer)
{
new_framebuffer->bind_framebuffer();
glClear(GL_COLOR_BUFFER_BIT);
glActiveTexture(pixel_accumulation_texture_unit);
framebuffer->bind_texture();
framebuffer->draw((float)output_width / (float)output_height);
new_framebuffer->bind_texture();
}
framebuffer = std::move(new_framebuffer);
}
// upload new source pixels
if(completed_texture_y)
{
glActiveTexture(source_data_texture_unit);
glTexSubImage2D( GL_TEXTURE_2D, 0,
0, 0,
InputBufferBuilderWidth, completed_texture_y,
formatForDepth(_buffer_builder->get_bytes_per_pixel()), GL_UNSIGNED_BYTE,
_buffer_builder->get_image_pointer());
}
struct RenderStage {
OpenGL::TextureTarget *const target;
OpenGL::Shader *const shader;
float clear_colour[3];
};
RenderStage composite_render_stages[] =
{
{compositeTexture.get(), composite_input_shader_program.get(), {0.0, 0.0, 0.0}},
{separatedTexture.get(), composite_separation_filter_program.get(), {0.0, 0.5, 0.5}},
{filteredYTexture.get(), composite_y_filter_shader_program.get(), {0.0, 0.5, 0.5}},
{filteredTexture.get(), composite_chrominance_filter_shader_program.get(), {0.0, 0.0, 0.0}},
{nullptr}
};
RenderStage rgb_render_stages[] =
{
{compositeTexture.get(), rgb_input_shader_program.get(), {0.0, 0.0, 0.0}},
{filteredTexture.get(), rgb_filter_shader_program.get(), {0.0, 0.0, 0.0}},
{nullptr}
};
RenderStage *active_pipeline = (_output_device == Television || !rgb_input_shader_program) ? composite_render_stages : rgb_render_stages;
// for television, update intermediate buffers and then draw; for a monitor, just draw
if(number_of_source_drawing_zones)
{
// all drawing will be from the source vertex array and without blending
glBindVertexArray(source_vertex_array);
glDisable(GL_BLEND);
while(active_pipeline->target)
{
// switch to the initial texture
active_pipeline->target->bind_framebuffer();
active_pipeline->shader->bind();
// clear as desired
if(number_of_clearing_zones)
{
glEnable(GL_SCISSOR_TEST);
glClearColor(active_pipeline->clear_colour[0], active_pipeline->clear_colour[1], active_pipeline->clear_colour[2], 1.0);
for(int c = 0; c < number_of_clearing_zones; c++)
{
glScissor(0, clearing_zones[c].location, IntermediateBufferWidth, clearing_zones[c].length);
glClear(GL_COLOR_BUFFER_BIT);
}
glDisable(GL_SCISSOR_TEST);
}
// draw as desired
drawArrayRanges(GL_LINES, SourceVertexSize, number_of_source_drawing_zones, source_drawing_zones);
active_pipeline++;
}
}
// transfer to framebuffer
framebuffer->bind_framebuffer();
if(number_of_output_drawing_zones)
{
glEnable(GL_BLEND);
// Ensure we're back on the output framebuffer, drawing from the output array buffer
glBindVertexArray(output_vertex_array);
// update uniforms (implicitly binding the shader)
if(_last_output_width != output_width || _last_output_height != output_height)
{
output_shader_program->set_output_size(output_width, output_height, _visible_area);
_last_output_width = output_width;
_last_output_height = output_height;
}
output_shader_program->bind();
// draw
drawArrayRanges(GL_TRIANGLE_STRIP, OutputVertexSize, number_of_output_drawing_zones, output_drawing_zones);
}
// copy framebuffer to the intended place
glDisable(GL_BLEND);
glBindFramebuffer(GL_FRAMEBUFFER, 0);
glViewport(0, 0, (GLsizei)output_width, (GLsizei)output_height);
glClear(GL_COLOR_BUFFER_BIT);
framebuffer->draw((float)output_width / (float)output_height);
_fence = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
_output_mutex->unlock();
}
void OpenGLOutputBuilder::set_openGL_context_will_change(bool should_delete_resources)
{
}
void OpenGLOutputBuilder::set_composite_sampling_function(const char *shader)
{
_composite_shader = strdup(shader);
}
void OpenGLOutputBuilder::set_rgb_sampling_function(const char *shader)
{
_rgb_shader = strdup(shader);
}
#pragma mark - Program compilation
void OpenGLOutputBuilder::prepare_composite_input_shaders()
{
composite_input_shader_program = OpenGL::IntermediateShader::make_source_conversion_shader(_composite_shader, _rgb_shader);
composite_input_shader_program->set_source_texture_unit(source_data_texture_unit);
composite_input_shader_program->set_output_size(IntermediateBufferWidth, IntermediateBufferHeight);
composite_separation_filter_program = OpenGL::IntermediateShader::make_chroma_luma_separation_shader();
composite_separation_filter_program->set_source_texture_unit(composite_texture_unit);
composite_separation_filter_program->set_output_size(IntermediateBufferWidth, IntermediateBufferHeight);
composite_y_filter_shader_program = OpenGL::IntermediateShader::make_luma_filter_shader();
composite_y_filter_shader_program->set_source_texture_unit(separated_texture_unit);
composite_y_filter_shader_program->set_output_size(IntermediateBufferWidth, IntermediateBufferHeight);
composite_chrominance_filter_shader_program = OpenGL::IntermediateShader::make_chroma_filter_shader();
composite_chrominance_filter_shader_program->set_source_texture_unit(filtered_y_texture_unit);
composite_chrominance_filter_shader_program->set_output_size(IntermediateBufferWidth, IntermediateBufferHeight);
}
void OpenGLOutputBuilder::prepare_rgb_input_shaders()
{
if(_rgb_shader)
{
rgb_input_shader_program = OpenGL::IntermediateShader::make_rgb_source_shader(_rgb_shader);
rgb_input_shader_program->set_source_texture_unit(source_data_texture_unit);
rgb_input_shader_program->set_output_size(IntermediateBufferWidth, IntermediateBufferHeight);
rgb_filter_shader_program = OpenGL::IntermediateShader::make_rgb_filter_shader();
rgb_filter_shader_program->set_source_texture_unit(composite_texture_unit);
rgb_filter_shader_program->set_output_size(IntermediateBufferWidth, IntermediateBufferHeight);
}
}
void OpenGLOutputBuilder::prepare_source_vertex_array()
{
if(composite_input_shader_program)
{
GLint inputPositionAttribute = composite_input_shader_program->get_attrib_location("inputPosition");
GLint outputPositionAttribute = composite_input_shader_program->get_attrib_location("outputPosition");
GLint phaseAndAmplitudeAttribute = composite_input_shader_program->get_attrib_location("phaseAndAmplitude");
GLint phaseTimeAttribute = composite_input_shader_program->get_attrib_location("phaseTime");
glBindVertexArray(source_vertex_array);
glEnableVertexAttribArray((GLuint)inputPositionAttribute);
glEnableVertexAttribArray((GLuint)outputPositionAttribute);
glEnableVertexAttribArray((GLuint)phaseAndAmplitudeAttribute);
glEnableVertexAttribArray((GLuint)phaseTimeAttribute);
const GLsizei vertexStride = SourceVertexSize;
glBindBuffer(GL_ARRAY_BUFFER, source_array_buffer);
glVertexAttribPointer((GLuint)inputPositionAttribute, 2, GL_UNSIGNED_SHORT, GL_FALSE, vertexStride, (void *)SourceVertexOffsetOfInputPosition);
glVertexAttribPointer((GLuint)outputPositionAttribute, 2, GL_UNSIGNED_SHORT, GL_FALSE, vertexStride, (void *)SourceVertexOffsetOfOutputPosition);
glVertexAttribPointer((GLuint)phaseAndAmplitudeAttribute, 2, GL_UNSIGNED_BYTE, GL_TRUE, vertexStride, (void *)SourceVertexOffsetOfPhaseAndAmplitude);
glVertexAttribPointer((GLuint)phaseTimeAttribute, 2, GL_UNSIGNED_SHORT, GL_FALSE, vertexStride, (void *)SourceVertexOffsetOfPhaseTime);
}
}
void OpenGLOutputBuilder::prepare_output_shader()
{
output_shader_program = OpenGL::OutputShader::make_shader("", "texture(texID, srcCoordinatesVarying).rgb", false);
output_shader_program->set_source_texture_unit(filtered_texture_unit);
}
void OpenGLOutputBuilder::prepare_output_vertex_array()
{
if(output_shader_program)
{
GLint positionAttribute = output_shader_program->get_attrib_location("position");
GLint textureCoordinatesAttribute = output_shader_program->get_attrib_location("srcCoordinates");
glBindVertexArray(output_vertex_array);
glEnableVertexAttribArray((GLuint)positionAttribute);
glEnableVertexAttribArray((GLuint)textureCoordinatesAttribute);
const GLsizei vertexStride = OutputVertexSize;
glBindBuffer(GL_ARRAY_BUFFER, output_array_buffer);
glVertexAttribPointer((GLuint)positionAttribute, 2, GL_UNSIGNED_SHORT, GL_FALSE, vertexStride, (void *)OutputVertexOffsetOfPosition);
glVertexAttribPointer((GLuint)textureCoordinatesAttribute, 2, GL_UNSIGNED_SHORT, GL_FALSE, vertexStride, (void *)OutputVertexOffsetOfTexCoord);
}
}
#pragma mark - Public Configuration
void OpenGLOutputBuilder::set_output_device(OutputDevice output_device)
{
if(_output_device != output_device)
{
_output_device = output_device;
_composite_src_output_y = 0;
_last_output_width = 0;
_last_output_height = 0;
}
}
void OpenGLOutputBuilder::set_timing(unsigned int input_frequency, unsigned int cycles_per_line, unsigned int height_of_display, unsigned int horizontal_scan_period, unsigned int vertical_scan_period, unsigned int vertical_period_divider)
{
_output_mutex->lock();
_input_frequency = input_frequency;
_cycles_per_line = cycles_per_line;
_height_of_display = height_of_display;
_horizontal_scan_period = horizontal_scan_period;
_vertical_scan_period = vertical_scan_period;
_vertical_period_divider = vertical_period_divider;
set_timing_uniforms();
_output_mutex->unlock();
}
#pragma mark - Internal Configuration
void OpenGLOutputBuilder::set_colour_space_uniforms()
{
GLfloat rgbToYUV[] = {0.299f, -0.14713f, 0.615f, 0.587f, -0.28886f, -0.51499f, 0.114f, 0.436f, -0.10001f};
GLfloat yuvToRGB[] = {1.0f, 1.0f, 1.0f, 0.0f, -0.39465f, 2.03211f, 1.13983f, -0.58060f, 0.0f};
GLfloat rgbToYIQ[] = {0.299f, 0.596f, 0.211f, 0.587f, -0.274f, -0.523f, 0.114f, -0.322f, 0.312f};
GLfloat yiqToRGB[] = {1.0f, 1.0f, 1.0f, 0.956f, -0.272f, -1.106f, 0.621f, -0.647f, 1.703f};
GLfloat *fromRGB, *toRGB;
switch(_colour_space)
{
case ColourSpace::YIQ:
fromRGB = rgbToYIQ;
toRGB = yiqToRGB;
break;
case ColourSpace::YUV:
fromRGB = rgbToYUV;
toRGB = yuvToRGB;
break;
}
if(composite_input_shader_program) composite_input_shader_program->set_colour_conversion_matrices(fromRGB, toRGB);
if(composite_chrominance_filter_shader_program) composite_chrominance_filter_shader_program->set_colour_conversion_matrices(fromRGB, toRGB);
}
void OpenGLOutputBuilder::set_timing_uniforms()
{
OpenGL::IntermediateShader *intermediate_shaders[] = {
composite_input_shader_program.get(),
composite_separation_filter_program.get(),
composite_y_filter_shader_program.get(),
composite_chrominance_filter_shader_program.get()
};
bool extends = false;
float phaseCyclesPerTick = (float)_colour_cycle_numerator / (float)(_colour_cycle_denominator * _cycles_per_line);
for(int c = 0; c < 3; c++)
{
if(intermediate_shaders[c]) intermediate_shaders[c]->set_phase_cycles_per_sample(phaseCyclesPerTick, extends);
extends = true;
}
if(output_shader_program) output_shader_program->set_timing(_height_of_display, _cycles_per_line, _horizontal_scan_period, _vertical_scan_period, _vertical_period_divider);
float colour_subcarrier_frequency = (float)_colour_cycle_numerator / (float)_colour_cycle_denominator;
if(composite_separation_filter_program) composite_separation_filter_program->set_separation_frequency(_cycles_per_line, colour_subcarrier_frequency);
if(composite_y_filter_shader_program) composite_y_filter_shader_program->set_filter_coefficients(_cycles_per_line, colour_subcarrier_frequency * 0.66f);
if(composite_chrominance_filter_shader_program) composite_chrominance_filter_shader_program->set_filter_coefficients(_cycles_per_line, colour_subcarrier_frequency * 0.5f);
if(rgb_filter_shader_program) rgb_filter_shader_program->set_filter_coefficients(_cycles_per_line, (float)_input_frequency * 0.5f);
}