mirror of
https://github.com/TomHarte/CLK.git
synced 2024-11-22 12:33:29 +00:00
107 lines
3.0 KiB
C++
107 lines
3.0 KiB
C++
//
|
|
// Video.hpp
|
|
// Clock Signal
|
|
//
|
|
// Created by Thomas Harte on 03/05/2019.
|
|
// Copyright © 2019 Thomas Harte. All rights reserved.
|
|
//
|
|
|
|
#ifndef Video_hpp
|
|
#define Video_hpp
|
|
|
|
#include "../../../Outputs/CRT/CRT.hpp"
|
|
#include "../../../ClockReceiver/ClockReceiver.hpp"
|
|
#include "DeferredAudio.hpp"
|
|
#include "DriveSpeedAccumulator.hpp"
|
|
|
|
namespace Apple::Macintosh {
|
|
|
|
constexpr HalfCycles line_length(704);
|
|
constexpr int number_of_lines = 370;
|
|
constexpr HalfCycles frame_length(line_length * HalfCycles(number_of_lines));
|
|
constexpr int sync_start = 36;
|
|
constexpr int sync_end = 38;
|
|
|
|
/*!
|
|
Models the 68000-era Macintosh video hardware, producing a 512x348 pixel image,
|
|
within a total scanning area of 370 lines, at 352 cycles per line.
|
|
|
|
This class also collects audio and 400kb drive-speed data, forwarding those values.
|
|
*/
|
|
class Video {
|
|
public:
|
|
/*!
|
|
Constructs an instance of @c Video sourcing its pixel data from @c ram and
|
|
providing audio and drive-speed bytes to @c audio and @c drive_speed_accumulator.
|
|
*/
|
|
Video(DeferredAudio &audio, DriveSpeedAccumulator &drive_speed_accumulator);
|
|
|
|
/*!
|
|
Sets the target device for video data.
|
|
*/
|
|
void set_scan_target(Outputs::Display::ScanTarget *scan_target);
|
|
|
|
/// Gets the current scan status.
|
|
Outputs::Display::ScanStatus get_scaled_scan_status() const;
|
|
|
|
/*!
|
|
Produces the next @c duration period of pixels.
|
|
*/
|
|
void run_for(HalfCycles duration);
|
|
|
|
/*!
|
|
Sets whether the alternate screen and/or audio buffers should be used to source data.
|
|
*/
|
|
void set_use_alternate_buffers(bool use_alternate_screen_buffer, bool use_alternate_audio_buffer);
|
|
|
|
/*!
|
|
Provides a base address and a mask indicating which parts of the generated video and audio/drive addresses are
|
|
actually decoded, accessing *word-sized memory*; e.g. for a 128kb Macintosh this should be (1 << 16) - 1 = 0xffff.
|
|
*/
|
|
void set_ram(uint16_t *ram, uint32_t mask);
|
|
|
|
/*!
|
|
@returns @c true if the video is currently outputting a vertical sync, @c false otherwise.
|
|
*/
|
|
bool vsync();
|
|
|
|
/*
|
|
@returns @c true if in @c offset half cycles from now, the video will be outputting pixels;
|
|
@c false otherwise.
|
|
*/
|
|
bool is_outputting(HalfCycles offset = HalfCycles(0)) {
|
|
const auto offset_position = frame_position_ + offset % frame_length;
|
|
const int column = int((offset_position % line_length).as_integral()) >> 4;
|
|
const int line = int((offset_position / line_length).as_integral());
|
|
return line < 342 && column < 32;
|
|
}
|
|
|
|
/*!
|
|
@returns the amount of time until there is next a transition on the
|
|
vsync signal.
|
|
*/
|
|
HalfCycles next_sequence_point();
|
|
|
|
private:
|
|
DeferredAudio &audio_;
|
|
DriveSpeedAccumulator &drive_speed_accumulator_;
|
|
|
|
Outputs::CRT::CRT crt_;
|
|
uint16_t *ram_ = nullptr;
|
|
uint32_t ram_mask_ = 0;
|
|
|
|
HalfCycles frame_position_;
|
|
|
|
size_t video_address_ = 0;
|
|
size_t audio_address_ = 0;
|
|
|
|
uint64_t *pixel_buffer_ = nullptr;
|
|
|
|
bool use_alternate_screen_buffer_ = false;
|
|
bool use_alternate_audio_buffer_ = false;
|
|
};
|
|
|
|
}
|
|
|
|
#endif /* Video_hpp */
|