mirror of
https://github.com/TomHarte/CLK.git
synced 2024-08-28 04:29:04 +00:00
144 lines
4.2 KiB
C++
144 lines
4.2 KiB
C++
//
|
|
// TextureBuilder.cpp
|
|
// Clock Signal
|
|
//
|
|
// Created by Thomas Harte on 08/03/2016.
|
|
// Copyright © 2016 Thomas Harte. All rights reserved.
|
|
//
|
|
|
|
#include "TextureBuilder.hpp"
|
|
#include "CRTOpenGL.hpp"
|
|
#include "OpenGL.hpp"
|
|
#include <string.h>
|
|
|
|
using namespace Outputs::CRT;
|
|
|
|
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;
|
|
}
|
|
}
|
|
|
|
TextureBuilder::TextureBuilder(size_t bytes_per_pixel, GLenum texture_unit) :
|
|
bytes_per_pixel_(bytes_per_pixel),
|
|
next_write_x_position_(0),
|
|
next_write_y_position_(0)
|
|
{
|
|
image_.resize(bytes_per_pixel * InputBufferBuilderWidth * InputBufferBuilderHeight);
|
|
glGenTextures(1, &texture_name_);
|
|
|
|
glActiveTexture(texture_unit);
|
|
glBindTexture(GL_TEXTURE_2D, texture_name_);
|
|
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(bytes_per_pixel), InputBufferBuilderWidth, InputBufferBuilderHeight, 0, formatForDepth(bytes_per_pixel), GL_UNSIGNED_BYTE, nullptr);
|
|
}
|
|
|
|
TextureBuilder::~TextureBuilder()
|
|
{
|
|
glDeleteTextures(1, &texture_name_);
|
|
}
|
|
|
|
uint8_t *TextureBuilder::allocate_write_area(size_t required_length)
|
|
{
|
|
if(next_write_y_position_ != InputBufferBuilderHeight)
|
|
{
|
|
last_allocation_amount_ = required_length;
|
|
|
|
if(next_write_x_position_ + required_length + 2 > InputBufferBuilderWidth)
|
|
{
|
|
next_write_x_position_ = 0;
|
|
next_write_y_position_++;
|
|
|
|
if(next_write_y_position_ == InputBufferBuilderHeight)
|
|
return nullptr;
|
|
}
|
|
|
|
write_x_position_ = next_write_x_position_ + 1;
|
|
write_y_position_ = next_write_y_position_;
|
|
write_target_pointer_ = (write_y_position_ * InputBufferBuilderWidth) + write_x_position_;
|
|
next_write_x_position_ += required_length + 2;
|
|
}
|
|
else return nullptr;
|
|
|
|
return &image_[write_target_pointer_ * bytes_per_pixel_];
|
|
}
|
|
|
|
bool TextureBuilder::is_full()
|
|
{
|
|
return (next_write_y_position_ == InputBufferBuilderHeight);
|
|
}
|
|
|
|
void TextureBuilder::reduce_previous_allocation_to(size_t actual_length)
|
|
{
|
|
if(next_write_y_position_ == InputBufferBuilderHeight) return;
|
|
|
|
uint8_t *const image_pointer = image_.data();
|
|
|
|
// correct if the writing cursor was reset while a client was writing
|
|
if(next_write_x_position_ == 0 && next_write_y_position_ == 0)
|
|
{
|
|
memmove(&image_pointer[bytes_per_pixel_], &image_pointer[write_target_pointer_ * bytes_per_pixel_], actual_length * bytes_per_pixel_);
|
|
write_target_pointer_ = 1;
|
|
last_allocation_amount_ = actual_length;
|
|
next_write_x_position_ = (uint16_t)(actual_length + 2);
|
|
write_x_position_ = 1;
|
|
write_y_position_ = 0;
|
|
}
|
|
|
|
// book end the allocation with duplicates of the first and last pixel, to protect
|
|
// against rounding errors when this run is drawn
|
|
memcpy( &image_pointer[(write_target_pointer_ - 1) * bytes_per_pixel_],
|
|
&image_pointer[write_target_pointer_ * bytes_per_pixel_],
|
|
bytes_per_pixel_);
|
|
|
|
memcpy( &image_pointer[(write_target_pointer_ + actual_length) * bytes_per_pixel_],
|
|
&image_pointer[(write_target_pointer_ + actual_length - 1) * bytes_per_pixel_],
|
|
bytes_per_pixel_);
|
|
|
|
// return any allocated length that wasn't actually used to the available pool
|
|
next_write_x_position_ -= (last_allocation_amount_ - actual_length);
|
|
}
|
|
|
|
uint16_t TextureBuilder::get_last_write_x_position()
|
|
{
|
|
return write_x_position_;
|
|
}
|
|
|
|
uint16_t TextureBuilder::get_last_write_y_position()
|
|
{
|
|
return write_y_position_;
|
|
}
|
|
|
|
void TextureBuilder::submit()
|
|
{
|
|
uint16_t height = write_y_position_ + (next_write_x_position_ ? 1 : 0);
|
|
next_write_x_position_ = next_write_y_position_ = 0;
|
|
|
|
glTexSubImage2D( GL_TEXTURE_2D, 0,
|
|
0, 0,
|
|
InputBufferBuilderWidth, height,
|
|
formatForDepth(bytes_per_pixel_), GL_UNSIGNED_BYTE,
|
|
image_.data());
|
|
}
|