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mirror of https://github.com/TomHarte/CLK.git synced 2024-12-25 03:32:01 +00:00

Uses const to ensure output_* are properly constrained.

This commit is contained in:
Thomas Harte 2018-08-18 21:36:48 -04:00
parent 17bf1a64bf
commit 33576aa2c4
2 changed files with 14 additions and 19 deletions

View File

@ -117,7 +117,7 @@ void VideoBase::set_character_rom(const std::vector<uint8_t> &character_rom) {
}
}
uint8_t *VideoBase::output_text(uint8_t *target, uint8_t *source, size_t length, size_t pixel_row) {
uint8_t *VideoBase::output_text(uint8_t *target, uint8_t *source, size_t length, size_t pixel_row) const {
const uint8_t inverses[] = {
0xff,
is_iie_ ? static_cast<uint8_t>(0xff) : static_cast<uint8_t>((flash_ / flash_length) * 0xff),
@ -144,11 +144,10 @@ uint8_t *VideoBase::output_text(uint8_t *target, uint8_t *source, size_t length,
graphics_carry_ = character_pattern & 0x01;
target += 7;
}
return target;
}
uint8_t *VideoBase::output_double_text(uint8_t *target, uint8_t *source, uint8_t *auxiliary_source, size_t length, size_t pixel_row) {
uint8_t *VideoBase::output_double_text(uint8_t *target, uint8_t *source, uint8_t *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>(
@ -183,11 +182,10 @@ uint8_t *VideoBase::output_double_text(uint8_t *target, uint8_t *source, uint8_t
graphics_carry_ = character_patterns[1] & 0x01;
target += 14;
}
return target;
}
uint8_t *VideoBase::output_low_resolution(uint8_t *target, uint8_t *source, size_t length, int row) {
uint8_t *VideoBase::output_low_resolution(uint8_t *target, uint8_t *source, size_t length, 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
@ -207,11 +205,10 @@ uint8_t *VideoBase::output_low_resolution(uint8_t *target, uint8_t *source, size
}
target += 14;
}
return target;
}
uint8_t *VideoBase::output_double_low_resolution(uint8_t *target, uint8_t *source, uint8_t *auxiliary_source, size_t length, int row) {
uint8_t *VideoBase::output_double_low_resolution(uint8_t *target, uint8_t *source, uint8_t *auxiliary_source, size_t length, int row) const {
const int row_shift = row&4;
for(size_t c = 0; c < length; ++c) {
if(c&1) {
@ -239,11 +236,10 @@ uint8_t *VideoBase::output_double_low_resolution(uint8_t *target, uint8_t *sourc
}
target += 14;
}
return target;
}
uint8_t *VideoBase::output_high_resolution(uint8_t *target, uint8_t *source, size_t length) {
uint8_t *VideoBase::output_high_resolution(uint8_t *target, uint8_t *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.
@ -271,7 +267,7 @@ uint8_t *VideoBase::output_high_resolution(uint8_t *target, uint8_t *source, siz
return target;
}
uint8_t *VideoBase::output_double_high_resolution(uint8_t *target, uint8_t *source, uint8_t *auxiliary_source, size_t length) {
uint8_t *VideoBase::output_double_high_resolution(uint8_t *target, uint8_t *source, uint8_t *auxiliary_source, size_t length) const {
for(size_t c = 0; c < length; ++c) {
target[0] = graphics_carry_;
target[1] = auxiliary_source[c] & 0x01;
@ -288,8 +284,7 @@ uint8_t *VideoBase::output_double_high_resolution(uint8_t *target, uint8_t *sour
target[12] = auxiliary_source[c] & 0x10;
target[13] = auxiliary_source[c] & 0x20;
graphics_carry_ = auxiliary_source[c] & 0x40;
pixel_pointer_ += 14;
target += 14;
}
return target;
}

View File

@ -178,7 +178,7 @@ class VideoBase {
// Graphics carry is the final level output in a fetch window;
// it carries on into the next if it's high resolution with
// the delay bit set.
uint8_t graphics_carry_ = 0;
mutable uint8_t graphics_carry_ = 0;
// This holds a copy of the character ROM. The regular character
// set is assumed to be in the first 64*8 bytes; the alternative
@ -198,37 +198,37 @@ class VideoBase {
Outputs 40-column text to @c target, using @c length bytes from @c source.
@return One byte after the final value written to @c target.
*/
uint8_t *output_text(uint8_t *target, uint8_t *source, size_t length, size_t pixel_row);
uint8_t *output_text(uint8_t *target, uint8_t *source, size_t length, size_t pixel_row) const;
/*!
Outputs 80-column text to @c target, drawing @c length columns from @c source and @c auxiliary_source.
@return One byte after the final value written to @c target.
*/
uint8_t *output_double_text(uint8_t *target, uint8_t *source, uint8_t *auxiliary_source, size_t length, size_t pixel_row);
uint8_t *output_double_text(uint8_t *target, uint8_t *source, uint8_t *auxiliary_source, size_t length, size_t pixel_row) const;
/*!
Outputs 40-column low-resolution graphics to @c target, drawing @c length columns from @c source.
@return One byte after the final value written to @c target.
*/
uint8_t *output_low_resolution(uint8_t *target, uint8_t *source, size_t length, int row);
uint8_t *output_low_resolution(uint8_t *target, uint8_t *source, size_t length, int row) const;
/*!
Outputs 80-column low-resolution graphics to @c target, drawing @c length columns from @c source and @c auxiliary_source.
@return One byte after the final value written to @c target.
*/
uint8_t *output_double_low_resolution(uint8_t *target, uint8_t *source, uint8_t *auxiliary_source, size_t length, int row);
uint8_t *output_double_low_resolution(uint8_t *target, uint8_t *source, uint8_t *auxiliary_source, size_t length, int row) const;
/*!
Outputs 40-column high-resolution graphics to @c target, drawing @c length columns from @c source.
@return One byte after the final value written to @c target.
*/
uint8_t *output_high_resolution(uint8_t *target, uint8_t *source, size_t length);
uint8_t *output_high_resolution(uint8_t *target, uint8_t *source, size_t length) const;
/*!
Outputs 80-column double-high-resolution graphics to @c target, drawing @c length columns from @c source.
@return One byte after the final value written to @c target.
*/
uint8_t *output_double_high_resolution(uint8_t *target, uint8_t *source, uint8_t *auxiliary_source, size_t length);
uint8_t *output_double_high_resolution(uint8_t *target, uint8_t *source, uint8_t *auxiliary_source, size_t length) const;
};
template <class BusHandler, bool is_iie> class Video: public VideoBase {