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CLK/Machines/AppleII/Video.cpp
Thomas Harte 16731661e8 Switches back to being explicit about the colour burst phase.
Some sort of phase inversion otherwise seems to be achievable by software that switch modes often.
2019-02-24 22:28:11 -05:00

341 lines
12 KiB
C++

//
// Video.cpp
// Clock Signal
//
// Created by Thomas Harte on 14/04/2018.
// Copyright 2018 Thomas Harte. All rights reserved.
//
#include "Video.hpp"
using namespace AppleII::Video;
VideoBase::VideoBase(bool is_iie, std::function<void(Cycles)> &&target) :
crt_(910, 1, Outputs::Display::Type::NTSC60, Outputs::Display::InputDataType::Luminance1),
is_iie_(is_iie),
deferrer_(std::move(target)) {
// Show only the centre 75% of the TV frame.
crt_.set_display_type(Outputs::Display::DisplayType::CompositeColour);
crt_.set_visible_area(Outputs::Display::Rect(0.118f, 0.122f, 0.77f, 0.77f));
// TODO: there seems to be some sort of bug whereby switching modes can cause
// a signal discontinuity that knocks phase out of whack. So it isn't safe to
// use default_colour_bursts elsewhere, though it otherwise should be. If/when
// it is, start doing so and return to setting the immediate phase up here.
// crt_.set_immediate_default_phase(0.5f);
character_zones[0].xor_mask = 0;
character_zones[0].address_mask = 0x3f;
character_zones[1].xor_mask = 0;
character_zones[1].address_mask = 0x3f;
character_zones[2].xor_mask = 0;
character_zones[2].address_mask = 0x3f;
character_zones[3].xor_mask = 0;
character_zones[3].address_mask = 0x3f;
if(is_iie) {
character_zones[0].xor_mask =
character_zones[2].xor_mask =
character_zones[3].xor_mask = 0xff;
character_zones[2].address_mask =
character_zones[3].address_mask = 0xff;
}
}
void VideoBase::set_scan_target(Outputs::Display::ScanTarget *scan_target) {
crt_.set_scan_target(scan_target);
}
void VideoBase::set_display_type(Outputs::Display::DisplayType display_type) {
crt_.set_display_type(display_type);
}
/*
Rote setters and getters.
*/
void VideoBase::set_alternative_character_set(bool alternative_character_set) {
set_alternative_character_set_ = alternative_character_set;
deferrer_.defer(Cycles(2), [=] {
alternative_character_set_ = alternative_character_set;
if(alternative_character_set) {
character_zones[1].address_mask = 0xff;
character_zones[1].xor_mask = 0;
} else {
character_zones[1].address_mask = 0x3f;
character_zones[1].xor_mask = flash_mask();
}
});
}
bool VideoBase::get_alternative_character_set() {
return set_alternative_character_set_;
}
void VideoBase::set_80_columns(bool columns_80) {
set_columns_80_ = columns_80;
deferrer_.defer(Cycles(2), [=] {
columns_80_ = columns_80;
});
}
bool VideoBase::get_80_columns() {
return set_columns_80_;
}
void VideoBase::set_80_store(bool store_80) {
set_store_80_ = store_80_ = store_80;
}
bool VideoBase::get_80_store() {
return set_store_80_;
}
void VideoBase::set_page2(bool page2) {
set_page2_ = page2_ = page2;
}
bool VideoBase::get_page2() {
return set_page2_;
}
void VideoBase::set_text(bool text) {
set_text_ = text;
deferrer_.defer(Cycles(2), [=] {
text_ = text;
});
}
bool VideoBase::get_text() {
return set_text_;
}
void VideoBase::set_mixed(bool mixed) {
set_mixed_ = mixed;
deferrer_.defer(Cycles(2), [=] {
mixed_ = mixed;
});
}
bool VideoBase::get_mixed() {
return set_mixed_;
}
void VideoBase::set_high_resolution(bool high_resolution) {
set_high_resolution_ = high_resolution;
deferrer_.defer(Cycles(2), [=] {
high_resolution_ = high_resolution;
});
}
bool VideoBase::get_high_resolution() {
return set_high_resolution_;
}
void VideoBase::set_annunciator_3(bool annunciator_3) {
set_annunciator_3_ = annunciator_3;
deferrer_.defer(Cycles(2), [=] {
annunciator_3_ = annunciator_3;
high_resolution_mask_ = annunciator_3_ ? 0x7f : 0xff;
});
}
bool VideoBase::get_annunciator_3() {
return set_annunciator_3_;
}
void VideoBase::set_character_rom(const std::vector<uint8_t> &character_rom) {
character_rom_ = character_rom;
// Flip all character contents based on the second line of the $ graphic.
if(character_rom_[0x121] == 0x3c || character_rom_[0x122] == 0x3c) {
for(auto &graphic : character_rom_) {
graphic =
((graphic & 0x01) ? 0x40 : 0x00) |
((graphic & 0x02) ? 0x20 : 0x00) |
((graphic & 0x04) ? 0x10 : 0x00) |
((graphic & 0x08) ? 0x08 : 0x00) |
((graphic & 0x10) ? 0x04 : 0x00) |
((graphic & 0x20) ? 0x02 : 0x00) |
((graphic & 0x40) ? 0x01 : 0x00);
}
}
}
void VideoBase::output_text(uint8_t *target, const uint8_t *const source, size_t length, size_t pixel_row) const {
for(size_t c = 0; c < length; ++c) {
const int character = source[c] & character_zones[source[c] >> 6].address_mask;
const uint8_t xor_mask = character_zones[source[c] >> 6].xor_mask;
const std::size_t character_address = static_cast<std::size_t>(character << 3) + pixel_row;
const uint8_t character_pattern = character_rom_[character_address] ^ xor_mask;
// The character ROM is output MSB to LSB rather than LSB to MSB.
target[0] = target[1] = character_pattern & 0x40;
target[2] = target[3] = character_pattern & 0x20;
target[4] = target[5] = character_pattern & 0x10;
target[6] = target[7] = character_pattern & 0x08;
target[8] = target[9] = character_pattern & 0x04;
target[10] = target[11] = character_pattern & 0x02;
target[12] = target[13] = character_pattern & 0x01;
graphics_carry_ = character_pattern & 0x01;
target += 14;
}
}
void VideoBase::output_double_text(uint8_t *target, const uint8_t *const source, const uint8_t *const auxiliary_source, size_t length, size_t pixel_row) const {
for(size_t c = 0; c < length; ++c) {
const std::size_t character_addresses[2] = {
static_cast<std::size_t>(
(auxiliary_source[c] & character_zones[auxiliary_source[c] >> 6].address_mask) << 3
) + pixel_row,
static_cast<std::size_t>(
(source[c] & character_zones[source[c] >> 6].address_mask) << 3
) + pixel_row
};
const uint8_t character_patterns[2] = {
static_cast<uint8_t>(
character_rom_[character_addresses[0]] ^ character_zones[auxiliary_source[c] >> 6].xor_mask
),
static_cast<uint8_t>(
character_rom_[character_addresses[1]] ^ character_zones[source[c] >> 6].xor_mask
)
};
// The character ROM is output MSB to LSB rather than LSB to MSB.
target[0] = character_patterns[0] & 0x40;
target[1] = character_patterns[0] & 0x20;
target[2] = character_patterns[0] & 0x10;
target[3] = character_patterns[0] & 0x08;
target[4] = character_patterns[0] & 0x04;
target[5] = character_patterns[0] & 0x02;
target[6] = character_patterns[0] & 0x01;
target[7] = character_patterns[1] & 0x40;
target[8] = character_patterns[1] & 0x20;
target[9] = character_patterns[1] & 0x10;
target[10] = character_patterns[1] & 0x08;
target[11] = character_patterns[1] & 0x04;
target[12] = character_patterns[1] & 0x02;
target[13] = character_patterns[1] & 0x01;
graphics_carry_ = character_patterns[1] & 0x01;
target += 14;
}
}
void VideoBase::output_low_resolution(uint8_t *target, const uint8_t *const source, size_t length, int column, int row) const {
const int row_shift = row&4;
for(size_t c = 0; c < length; ++c) {
// Low-resolution graphics mode shifts the colour code on a loop, but has to account for whether this
// 14-sample output window is starting at the beginning of a colour cycle or halfway through.
if((column + static_cast<int>(c))&1) {
target[0] = target[4] = target[8] = target[12] = (source[c] >> row_shift) & 4;
target[1] = target[5] = target[9] = target[13] = (source[c] >> row_shift) & 8;
target[2] = target[6] = target[10] = (source[c] >> row_shift) & 1;
target[3] = target[7] = target[11] = (source[c] >> row_shift) & 2;
graphics_carry_ = (source[c] >> row_shift) & 8;
} else {
target[0] = target[4] = target[8] = target[12] = (source[c] >> row_shift) & 1;
target[1] = target[5] = target[9] = target[13] = (source[c] >> row_shift) & 2;
target[2] = target[6] = target[10] = (source[c] >> row_shift) & 4;
target[3] = target[7] = target[11] = (source[c] >> row_shift) & 8;
graphics_carry_ = (source[c] >> row_shift) & 2;
}
target += 14;
}
}
void VideoBase::output_fat_low_resolution(uint8_t *target, const uint8_t *const source, size_t length, int column, int row) const {
const int row_shift = row&4;
for(size_t c = 0; c < length; ++c) {
// Fat low-resolution mode appears not to do anything to try to make odd and
// even columns compatible.
target[0] = target[1] = target[8] = target[9] = (source[c] >> row_shift) & 1;
target[2] = target[3] = target[10] = target[11] = (source[c] >> row_shift) & 2;
target[4] = target[5] = target[12] = target[13] = (source[c] >> row_shift) & 4;
target[6] = target[7] = (source[c] >> row_shift) & 8;
graphics_carry_ = (source[c] >> row_shift) & 4;
target += 14;
}
}
void VideoBase::output_double_low_resolution(uint8_t *target, const uint8_t *const source, const uint8_t *const auxiliary_source, size_t length, int column, int row) const {
const int row_shift = row&4;
for(size_t c = 0; c < length; ++c) {
if((column + static_cast<int>(c))&1) {
target[0] = target[4] = (auxiliary_source[c] >> row_shift) & 2;
target[1] = target[5] = (auxiliary_source[c] >> row_shift) & 4;
target[2] = target[6] = (auxiliary_source[c] >> row_shift) & 8;
target[3] = (auxiliary_source[c] >> row_shift) & 1;
target[8] = target[12] = (source[c] >> row_shift) & 4;
target[9] = target[13] = (source[c] >> row_shift) & 8;
target[10] = (source[c] >> row_shift) & 1;
target[7] = target[11] = (source[c] >> row_shift) & 2;
graphics_carry_ = (source[c] >> row_shift) & 8;
} else {
target[0] = target[4] = (auxiliary_source[c] >> row_shift) & 8;
target[1] = target[5] = (auxiliary_source[c] >> row_shift) & 1;
target[2] = target[6] = (auxiliary_source[c] >> row_shift) & 2;
target[3] = (auxiliary_source[c] >> row_shift) & 4;
target[8] = target[12] = (source[c] >> row_shift) & 1;
target[9] = target[13] = (source[c] >> row_shift) & 2;
target[10] = (source[c] >> row_shift) & 4;
target[7] = target[11] = (source[c] >> row_shift) & 8;
graphics_carry_ = (source[c] >> row_shift) & 2;
}
target += 14;
}
}
void VideoBase::output_high_resolution(uint8_t *target, const uint8_t *const source, size_t length) const {
for(size_t c = 0; c < length; ++c) {
// High resolution graphics shift out LSB to MSB, optionally with a delay of half a pixel.
// If there is a delay, the previous output level is held to bridge the gap.
// Delays may be ignored on a IIe if Annunciator 3 is set; that's the state that
// high_resolution_mask_ models.
if(source[c] & high_resolution_mask_ & 0x80) {
target[0] = graphics_carry_;
target[1] = target[2] = source[c] & 0x01;
target[3] = target[4] = source[c] & 0x02;
target[5] = target[6] = source[c] & 0x04;
target[7] = target[8] = source[c] & 0x08;
target[9] = target[10] = source[c] & 0x10;
target[11] = target[12] = source[c] & 0x20;
target[13] = source[c] & 0x40;
} else {
target[0] = target[1] = source[c] & 0x01;
target[2] = target[3] = source[c] & 0x02;
target[4] = target[5] = source[c] & 0x04;
target[6] = target[7] = source[c] & 0x08;
target[8] = target[9] = source[c] & 0x10;
target[10] = target[11] = source[c] & 0x20;
target[12] = target[13] = source[c] & 0x40;
}
graphics_carry_ = source[c] & 0x40;
target += 14;
}
}
void VideoBase::output_double_high_resolution(uint8_t *target, const uint8_t *const source, const uint8_t *const auxiliary_source, size_t length) const {
for(size_t c = 0; c < length; ++c) {
target[0] = auxiliary_source[c] & 0x01;
target[1] = auxiliary_source[c] & 0x02;
target[2] = auxiliary_source[c] & 0x04;
target[3] = auxiliary_source[c] & 0x08;
target[4] = auxiliary_source[c] & 0x10;
target[5] = auxiliary_source[c] & 0x20;
target[6] = auxiliary_source[c] & 0x40;
target[7] = source[c] & 0x01;
target[8] = source[c] & 0x02;
target[9] = source[c] & 0x04;
target[10] = source[c] & 0x08;
target[11] = source[c] & 0x10;
target[12] = source[c] & 0x20;
target[13] = source[c] & 0x40;
graphics_carry_ = auxiliary_source[c] & 0x40;
target += 14;
}
}