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mirror of https://github.com/TomHarte/CLK.git synced 2024-12-23 20:29:42 +00:00

Move BitplaneShifter adjacent to expand_bitplane_byte.

This commit is contained in:
Thomas Harte 2021-11-26 18:29:09 -05:00
parent 8fc27dc292
commit 33bfa1b81c

View File

@ -31,6 +31,41 @@ static_assert(expand_bitplane_byte(0x00) == 0x00'00'00'00'00'00'00'00);
}
// MARK: - BitplaneShifter.
void BitplaneShifter::set(const BitplaneData &previous, const BitplaneData &next, int odd_delay, int even_delay) {
const uint16_t planes[6] = {
uint16_t(((previous[0] << 16) | next[0]) >> even_delay),
uint16_t(((previous[1] << 16) | next[1]) >> odd_delay),
uint16_t(((previous[2] << 16) | next[2]) >> even_delay),
uint16_t(((previous[3] << 16) | next[3]) >> odd_delay),
uint16_t(((previous[4] << 16) | next[4]) >> even_delay),
uint16_t(((previous[5] << 16) | next[5]) >> odd_delay),
};
// Swizzle bits into the form:
//
// [b5 b3 b1 b4 b2 b0]
//
// ... and assume a suitably adjusted palette is in use elsewhere.
// This makes dual playfields very easy to separate.
data_[0] =
(expand_bitplane_byte(uint8_t(planes[0])) << 0) |
(expand_bitplane_byte(uint8_t(planes[2])) << 1) |
(expand_bitplane_byte(uint8_t(planes[4])) << 2) |
(expand_bitplane_byte(uint8_t(planes[1])) << 3) |
(expand_bitplane_byte(uint8_t(planes[3])) << 4) |
(expand_bitplane_byte(uint8_t(planes[5])) << 5);
data_[1] =
(expand_bitplane_byte(uint8_t(planes[0] >> 8)) << 0) |
(expand_bitplane_byte(uint8_t(planes[2] >> 8)) << 1) |
(expand_bitplane_byte(uint8_t(planes[4] >> 8)) << 2) |
(expand_bitplane_byte(uint8_t(planes[1] >> 8)) << 3) |
(expand_bitplane_byte(uint8_t(planes[3] >> 8)) << 4) |
(expand_bitplane_byte(uint8_t(planes[5] >> 8)) << 5);
}
// MARK: - Bitplanes.
bool Bitplanes::advance_dma(int cycle) {
@ -95,38 +130,3 @@ void Bitplanes::set_control(uint16_t control) {
plane_count_ = 4;
}
}
// MARK: - BitplaneShifter
void BitplaneShifter::set(const BitplaneData &previous, const BitplaneData &next, int odd_delay, int even_delay) {
const uint16_t planes[6] = {
uint16_t(((previous[0] << 16) | next[0]) >> even_delay),
uint16_t(((previous[1] << 16) | next[1]) >> odd_delay),
uint16_t(((previous[2] << 16) | next[2]) >> even_delay),
uint16_t(((previous[3] << 16) | next[3]) >> odd_delay),
uint16_t(((previous[4] << 16) | next[4]) >> even_delay),
uint16_t(((previous[5] << 16) | next[5]) >> odd_delay),
};
// Swizzle bits into the form:
//
// [b5 b3 b1 b4 b2 b0]
//
// ... and assume a suitably adjusted palette is in use elsewhere.
// This makes dual playfields very easy to separate.
data_[0] =
(expand_bitplane_byte(uint8_t(planes[0])) << 0) |
(expand_bitplane_byte(uint8_t(planes[2])) << 1) |
(expand_bitplane_byte(uint8_t(planes[4])) << 2) |
(expand_bitplane_byte(uint8_t(planes[1])) << 3) |
(expand_bitplane_byte(uint8_t(planes[3])) << 4) |
(expand_bitplane_byte(uint8_t(planes[5])) << 5);
data_[1] =
(expand_bitplane_byte(uint8_t(planes[0] >> 8)) << 0) |
(expand_bitplane_byte(uint8_t(planes[2] >> 8)) << 1) |
(expand_bitplane_byte(uint8_t(planes[4] >> 8)) << 2) |
(expand_bitplane_byte(uint8_t(planes[1] >> 8)) << 3) |
(expand_bitplane_byte(uint8_t(planes[3] >> 8)) << 4) |
(expand_bitplane_byte(uint8_t(planes[5] >> 8)) << 5);
}