djsundog
/
circuitpython
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Fix off by one error in OnDiskBitmap 

It resulted in the first row of pixels being pulled for out of bounds.

Fixes #1801
This commit is contained in:
Scott Shawcroft 2019-04-17 15:17:11 -07:00
parent 49c4c1e2ac
commit c372567330
No known key found for this signature in database
GPG Key ID: FD0EDC4B6C53CA59
1 changed files with 7 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
shared-module/displayio/OnDiskBitmap.c
View File

@ -68,7 +68,7 @@ void common_hal_displayio_ondiskbitmap_construct(displayio_ondiskbitmap_t *self,
self->r_bitmask = read_word(bmp_header, 27);
self->g_bitmask = read_word(bmp_header, 29);
self->b_bitmask = read_word(bmp_header, 31);
} else { // no compression or short header means 5:5:5
self->r_bitmask = 0x7c00;
self->g_bitmask = 0x3e0;
@ -114,7 +114,7 @@ void common_hal_displayio_ondiskbitmap_construct(displayio_ondiskbitmap_t *self,
}
self->stride = (bit_stride / 8);
}
}
@ -123,12 +123,13 @@ uint32_t common_hal_displayio_ondiskbitmap_get_pixel(displayio_ondiskbitmap_t *s
if (x < 0 || x >= self->width || y < 0 || y >= self->height) {
return 0;
}
uint32_t location;
uint8_t bytes_per_pixel = (self->bits_per_pixel / 8) ? (self->bits_per_pixel /8) : 1;
if (self->bits_per_pixel >= 8){
location = self->data_offset + (self->height - y) * self->stride + x * bytes_per_pixel;
location = self->data_offset + (self->height - y - 1) * self->stride + x * bytes_per_pixel;
} else {
location = self->data_offset + (self->height - y) * self->stride + x / 8;
location = self->data_offset + (self->height - y - 1) * self->stride + x / 8;
}
// We don't cache here because the underlying FS caches sectors.
f_lseek(&self->file->fp, location);
@ -140,7 +141,7 @@ uint32_t common_hal_displayio_ondiskbitmap_get_pixel(displayio_ondiskbitmap_t *s
uint8_t red;
uint8_t green;
uint8_t blue;
if (self->bits_per_pixel == 1){
if (self->bits_per_pixel == 1) {
uint8_t bit_offset = x%8;
tmp = ( pixel_data & (0x80 >> (bit_offset))) >> (7 - bit_offset);
if (tmp == 1) {
@ -148,7 +149,7 @@ uint32_t common_hal_displayio_ondiskbitmap_get_pixel(displayio_ondiskbitmap_t *s
} else {
return 0x00000000;
}
} else if (bytes_per_pixel == 1){
} else if (bytes_per_pixel == 1) {
blue = ((self->palette_data[pixel_data] & 0xFF) >> 0);
red = ((self->palette_data[pixel_data] & 0xFF0000) >> 16);
green = ((self->palette_data[pixel_data] & 0xFF00) >> 8);