mirror of
https://github.com/TomHarte/CLK.git
synced 2024-07-08 15:29:09 +00:00
109 lines
3.8 KiB
C++
109 lines
3.8 KiB
C++
//
|
|
// OutputShader.hpp
|
|
// Clock Signal
|
|
//
|
|
// Created by Thomas Harte on 27/04/2016.
|
|
// Copyright 2016 Thomas Harte. All rights reserved.
|
|
//
|
|
|
|
#ifndef OutputShader_hpp
|
|
#define OutputShader_hpp
|
|
|
|
#include "Shader.hpp"
|
|
#include "../../ScanTarget.hpp"
|
|
#include <memory>
|
|
|
|
namespace OpenGL {
|
|
|
|
class OutputShader: public Shader {
|
|
public:
|
|
enum class Input {
|
|
/// A 2d vector; the first element is the horizontal start of this scan, the second element is the end.
|
|
Horizontal,
|
|
/// A 2d vector; the first element is the vertical start of this scan, the second element is the end.
|
|
Vertical
|
|
};
|
|
|
|
/*!
|
|
Obtains the name of a designated input. Designated inputs are guaranteed to have the same attribute location
|
|
across multiple instances of OutputShader. So binding a vertex array to these inputs for any instance of
|
|
OutputShader allows that array to work with all instances of OutputShader.
|
|
|
|
@param input The input to query.
|
|
@returns The name used in this shader's source for the nominated input.
|
|
*/
|
|
static std::string get_input_name(Input input);
|
|
|
|
/*!
|
|
Constructs and returns an instance of OutputShader. OutputShaders are intended to read source data
|
|
from a texture and draw a single raster scan containing that data as output.
|
|
|
|
Does not catch any of the exceptions potentially thrown by `Shader::Shader`.
|
|
|
|
All instances of OutputShader are guaranteed to use the same attribute locations for their inputs.
|
|
|
|
@param fragment_methods A block of code that will appear within the global area of the fragment shader.
|
|
|
|
@param colour_expression An expression that should evaluate to a `vec3` indicating the colour at the current location. The
|
|
decision should be a function of the uniform `texID`, which will be either a `usampler2D` or a `sampler2D` as per the
|
|
`use_usampler` parameter, and the inputs `srcCoordinatesVarying` which is a location within the texture from which to
|
|
take the source value, and `iSrcCoordinatesVarying` which is a value proportional to `srcCoordinatesVarying` but scaled
|
|
so that one unit equals one source sample.
|
|
|
|
@param use_usampler Dictates the type of the `texID` uniform; will be a `usampler2D` if this parameter is `true`, a
|
|
`sampler2D` otherwise.
|
|
|
|
@returns an instance of OutputShader.
|
|
*/
|
|
static std::unique_ptr<OutputShader> make_shader(const char *fragment_methods, const char *colour_expression, bool use_usampler);
|
|
using Shader::Shader;
|
|
|
|
/*!
|
|
Queues configuration for output to an area of `output_width` and `output_height` pixels, ensuring
|
|
the largest possible drawing size that allows everything within `visible_area` to be visible, to
|
|
occur upon the next `bind`.
|
|
*/
|
|
void set_output_size(unsigned int output_width, unsigned int output_height, Outputs::Display::Rect visible_area);
|
|
|
|
/*!
|
|
Queues setting of the texture unit (as an enum, e.g. `GL_TEXTURE0`) for source data upon the next `bind`.
|
|
*/
|
|
void set_source_texture_unit(GLenum unit);
|
|
|
|
/*!
|
|
Queues configuring this shader's understanding of how to map from the source vertex stream to screen coordinates,
|
|
to occur upon the next `bind`.
|
|
*/
|
|
void set_timing(unsigned int height_of_display, unsigned int cycles_per_line, unsigned int horizontal_scan_period, unsigned int vertical_scan_period, unsigned int vertical_period_divider);
|
|
|
|
/*!
|
|
*/
|
|
void set_origin_is_double_height(bool is_double_height);
|
|
|
|
void set_gamma_ratio(float ratio);
|
|
|
|
/*!
|
|
Sets the proportion of the input area that should be considered the whole width: 1.0 means use all available
|
|
space, 0.5 means use half, etc.
|
|
*/
|
|
void set_input_width_scaler(float input_scaler);
|
|
|
|
/*!
|
|
@returns The location, in eye coordinates, of the left edge of the output area.
|
|
*/
|
|
float get_left_extent();
|
|
|
|
/*!
|
|
@returns The location, in eye coordinates, of the right edge of the output area.
|
|
*/
|
|
float get_right_extent();
|
|
|
|
private:
|
|
float left_extent_ = 0.0f;
|
|
float right_extent_ = 0.0f;
|
|
};
|
|
|
|
}
|
|
|
|
#endif /* OutputShader_hpp */
|