extmod/modframebuf: Optimise fill and fill_rect methods.

Fill is a very common operation (eg to clear the screen) and it is worth
optimising it, by providing a specialised fill_rect function for each
framebuffer format.

This patch improved the speed of fill by 10 times for a 16-bit display
with 160*128 pixels.
This commit is contained in:
Damien George 2016-12-01 16:51:31 +11:00
parent 81e171b7bb
commit a081b49d55

View File

@ -44,10 +44,12 @@ typedef struct _mp_obj_framebuf_t {
typedef void (*setpixel_t)(const mp_obj_framebuf_t*, int, int, uint32_t);
typedef uint32_t (*getpixel_t)(const mp_obj_framebuf_t*, int, int);
typedef void (*fill_rect_t)(const mp_obj_framebuf_t *, int, int, int, int, uint32_t);
typedef struct _mp_framebuf_p_t {
setpixel_t setpixel;
getpixel_t getpixel;
fill_rect_t fill_rect;
} mp_framebuf_p_t;
// Functions for MVLSB format
@ -62,6 +64,18 @@ STATIC uint32_t mvlsb_getpixel(const mp_obj_framebuf_t *fb, int x, int y) {
return (((uint8_t*)fb->buf)[(y >> 3) * fb->stride + x] >> (y & 0x07)) & 0x01;
}
STATIC void mvlsb_fill_rect(const mp_obj_framebuf_t *fb, int x, int y, int w, int h, uint32_t col) {
while (h--) {
uint8_t *b = &((uint8_t*)fb->buf)[(y >> 3) * fb->stride + x];
uint8_t offset = y & 0x07;
for (int ww = w; ww; --ww) {
*b = (*b & ~(0x01 << offset)) | ((col != 0) << offset);
++b;
}
++y;
}
}
// Functions for RGB565 format
STATIC void rgb565_setpixel(const mp_obj_framebuf_t *fb, int x, int y, uint32_t color) {
@ -72,13 +86,23 @@ STATIC uint32_t rgb565_getpixel(const mp_obj_framebuf_t *fb, int x, int y) {
return ((uint16_t*)fb->buf)[x + y * fb->stride];
}
STATIC void rgb565_fill_rect(const mp_obj_framebuf_t *fb, int x, int y, int w, int h, uint32_t colour) {
uint16_t *b = &((uint16_t*)fb->buf)[x + y * fb->stride];
while (h--) {
for (int ww = w; ww; --ww) {
*b++ = colour;
}
b += fb->stride - w;
}
}
// constants for formats
#define FRAMEBUF_MVLSB (0)
#define FRAMEBUF_RGB565 (1)
STATIC mp_framebuf_p_t formats[] = {
[FRAMEBUF_MVLSB] = {mvlsb_setpixel, mvlsb_getpixel},
[FRAMEBUF_RGB565] = {rgb565_setpixel, rgb565_getpixel},
[FRAMEBUF_MVLSB] = {mvlsb_setpixel, mvlsb_getpixel, mvlsb_fill_rect},
[FRAMEBUF_RGB565] = {rgb565_setpixel, rgb565_getpixel, rgb565_fill_rect},
};
static inline void setpixel(const mp_obj_framebuf_t *fb, int x, int y, uint32_t color) {
@ -123,11 +147,7 @@ STATIC mp_obj_t framebuf_make_new(const mp_obj_type_t *type, size_t n_args, size
STATIC mp_obj_t framebuf_fill(mp_obj_t self_in, mp_obj_t col_in) {
mp_obj_framebuf_t *self = MP_OBJ_TO_PTR(self_in);
mp_int_t col = mp_obj_get_int(col_in);
for (int y = 0; y < self->height; ++y) {
for (int x = 0; x < self->width; ++x) {
setpixel(self, x, y, col);
}
}
formats[self->format].fill_rect(self, 0, 0, self->width, self->height, col);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(framebuf_fill_obj, framebuf_fill);
@ -153,11 +173,8 @@ STATIC mp_obj_t framebuf_fill_rect(size_t n_args, const mp_obj_t *args) {
x = MAX(MIN(x, self->width), 0);
y = MAX(MIN(y, self->height), 0);
for (; y < yend; ++y) {
for (int xc = x; xc < xend; ++xc) {
setpixel(self, xc, y, color);
}
}
formats[self->format].fill_rect(self, x, y, xend - x, yend - y, color);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(framebuf_fill_rect_obj, 6, 6, framebuf_fill_rect);