Files
jsix_import/src/drivers/fb/screen.cpp
Justin C. Miller 572fade7ff [fb] Use rep stosl for screen fill
This is mostly cleanup after fighting the double buffering bug - bring
back rep stosl for screen fill, and move draw_pixel to be an inline
function.
2021-02-05 23:55:42 -08:00

49 lines
1.1 KiB
C++

#include <stdlib.h>
#include <string.h>
#include "screen.h"
screen::screen(volatile void *addr, unsigned hres, unsigned vres, unsigned scanline, pixel_order order) :
m_fb(static_cast<volatile pixel_t *>(addr)),
m_order(order),
m_scanline(scanline),
m_resx(hres),
m_resy(vres)
{
const size_t size = scanline * vres;
m_back = reinterpret_cast<pixel_t*>(malloc(size * sizeof(pixel_t)));
}
screen::pixel_t
screen::color(uint8_t r, uint8_t g, uint8_t b) const
{
switch (m_order) {
case pixel_order::bgr8:
return
(static_cast<uint32_t>(b) << 0) |
(static_cast<uint32_t>(g) << 8) |
(static_cast<uint32_t>(r) << 16);
case pixel_order::rgb8:
return
(static_cast<uint32_t>(r) << 0) |
(static_cast<uint32_t>(g) << 8) |
(static_cast<uint32_t>(b) << 16);
}
}
void
screen::fill(pixel_t color)
{
const size_t len = m_scanline * m_resy;
asm volatile ( "rep stosl" : :
"a"(color), "c"(len), "D"(m_back) );
}
void
screen::update()
{
const size_t len = m_scanline * m_resy * sizeof(pixel_t);
asm volatile ( "rep movsb" : :
"c"(len), "S"(m_back), "D"(m_fb) );
}