circuitpython/shared-module/displayio/OnDiskBitmap.c
2025-04-24 14:59:07 -07:00

224 lines
8.4 KiB
C

// This file is part of the CircuitPython project: https://circuitpython.org
//
// SPDX-FileCopyrightText: Copyright (c) 2018 Scott Shawcroft for Adafruit Industries
// SPDX-FileCopyrightText: Copyright (c) 2025 SamantazFox
//
// SPDX-License-Identifier: MIT
#include "shared-bindings/displayio/OnDiskBitmap.h"
#include "shared-bindings/displayio/ColorConverter.h"
#include "shared-bindings/displayio/Palette.h"
#include "shared-module/displayio/ColorConverter.h"
#include "shared-module/displayio/Palette.h"
#include <string.h>
#include "py/mperrno.h"
#include "py/runtime.h"
#define DISPLAYIO_ODBMP_DEBUG(...) (void)0
// #define DISPLAYIO_ODBMP_DEBUG(...) mp_printf(&mp_plat_print __VA_OPT__(,) __VA_ARGS__)
static uint32_t read_word(uint16_t *bmp_header, uint16_t index) {
return bmp_header[index] | bmp_header[index + 1] << 16;
}
void common_hal_displayio_ondiskbitmap_construct(displayio_ondiskbitmap_t *self, pyb_file_obj_t *file) {
// Load the wave
self->file = file;
uint16_t bmp_header[69];
f_rewind(&self->file->fp);
UINT bytes_read;
// Read the minimum amount of bytes required to parse a BITMAPCOREHEADER.
// If needed, we will read more bytes down below.
if (f_read(&self->file->fp, bmp_header, 26, &bytes_read) != FR_OK) {
mp_raise_OSError(MP_EIO);
}
DISPLAYIO_ODBMP_DEBUG("bytes_read: %d\n", bytes_read);
if (bytes_read != 26 || memcmp(bmp_header, "BM", 2) != 0) {
mp_arg_error_invalid(MP_QSTR_file);
}
// Read header size to determine if more header bytes needs to be read.
uint32_t header_size = read_word(bmp_header, 7);
DISPLAYIO_ODBMP_DEBUG("header_size: %d\n", header_size);
if (header_size == 40 || header_size == 108 || header_size == 124) {
// Read the remaining header bytes
if (f_read(&self->file->fp, bmp_header + 13, header_size - 12, &bytes_read) != FR_OK) {
mp_raise_OSError(MP_EIO);
}
DISPLAYIO_ODBMP_DEBUG("bytes_read: %d\n", bytes_read);
if (bytes_read != (header_size - 12)) {
mp_arg_error_invalid(MP_QSTR_file);
}
} else if (header_size != 12) {
mp_raise_ValueError_varg(MP_ERROR_TEXT("Only Windows format, uncompressed BMP supported: given header size is %d"), header_size);
}
uint32_t compression = read_word(bmp_header, 15);
DISPLAYIO_ODBMP_DEBUG("compression: %d\n", compression);
// 0 is uncompressed; 3 is bitfield compressed. 1 and 2 are RLE compression.
if (compression != 0 && compression != 3) {
mp_raise_ValueError(MP_ERROR_TEXT("RLE-compressed BMP not supported"));
}
// We can't cast because we're not aligned.
self->data_offset = read_word(bmp_header, 5);
self->bitfield_compressed = (compression == 3);
self->bits_per_pixel = bmp_header[14];
self->width = read_word(bmp_header, 9);
self->height = read_word(bmp_header, 11);
DISPLAYIO_ODBMP_DEBUG("data offset: %d\n", self->data_offset);
DISPLAYIO_ODBMP_DEBUG("width: %d\n", self->width);
DISPLAYIO_ODBMP_DEBUG("height: %d\n", self->height);
DISPLAYIO_ODBMP_DEBUG("bpp: %d\n", self->bits_per_pixel);
displayio_colorconverter_t *colorconverter =
mp_obj_malloc(displayio_colorconverter_t, &displayio_colorconverter_type);
common_hal_displayio_colorconverter_construct(colorconverter, false, DISPLAYIO_COLORSPACE_RGB888);
self->colorconverter = colorconverter;
if (self->bits_per_pixel == 16) {
if (((header_size >= 56)) || (self->bitfield_compressed)) {
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;
self->b_bitmask = 0x1f;
}
} else if (self->bits_per_pixel <= 8) { // indexed
uint32_t number_of_colors = 0;
if (header_size >= 40) {
number_of_colors = read_word(bmp_header, 23);
}
if (number_of_colors == 0) {
number_of_colors = 1 << self->bits_per_pixel;
}
displayio_palette_t *palette = mp_obj_malloc(displayio_palette_t, &displayio_palette_type);
common_hal_displayio_palette_construct(palette, number_of_colors, false);
if (number_of_colors > 1) {
uint16_t palette_size = number_of_colors * sizeof(uint32_t);
uint16_t palette_offset = 0xe + header_size;
uint32_t *palette_data = m_malloc_without_collect(palette_size);
f_rewind(&self->file->fp);
f_lseek(&self->file->fp, palette_offset);
UINT palette_bytes_read;
if (f_read(&self->file->fp, palette_data, palette_size, &palette_bytes_read) != FR_OK) {
mp_raise_OSError(MP_EIO);
}
if (palette_bytes_read != palette_size) {
mp_raise_ValueError(MP_ERROR_TEXT("Unable to read color palette data"));
}
for (uint16_t i = 0; i < number_of_colors; i++) {
common_hal_displayio_palette_set_color(palette, i, palette_data[i]);
}
#if MICROPY_MALLOC_USES_ALLOCATED_SIZE
m_free(palette_data, palette_size);
#else
m_free(palette_data);
#endif
} else {
common_hal_displayio_palette_set_color(palette, 0, 0x0);
common_hal_displayio_palette_set_color(palette, 1, 0xffffff);
}
self->palette = palette;
}
uint8_t bytes_per_pixel = (self->bits_per_pixel / 8) ? (self->bits_per_pixel / 8) : 1;
uint8_t pixels_per_byte = 8 / self->bits_per_pixel;
if (pixels_per_byte == 0) {
self->stride = (self->width * bytes_per_pixel);
// Rows are word aligned.
if (self->stride % 4 != 0) {
self->stride += 4 - self->stride % 4;
}
} else {
uint32_t bit_stride = self->width * self->bits_per_pixel;
if (bit_stride % 32 != 0) {
bit_stride += 32 - bit_stride % 32;
}
self->stride = (bit_stride / 8);
}
}
uint32_t common_hal_displayio_ondiskbitmap_get_pixel(displayio_ondiskbitmap_t *self,
int16_t x, int16_t y) {
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;
uint8_t pixels_per_byte = 8 / self->bits_per_pixel;
if (pixels_per_byte == 0) {
location = self->data_offset + (self->height - y - 1) * self->stride + x * bytes_per_pixel;
} else {
location = self->data_offset + (self->height - y - 1) * self->stride + x / pixels_per_byte;
}
// We don't cache here because the underlying FS caches sectors.
f_lseek(&self->file->fp, location);
UINT bytes_read;
uint32_t pixel_data = 0;
uint32_t result = f_read(&self->file->fp, &pixel_data, bytes_per_pixel, &bytes_read);
if (result == FR_OK) {
uint32_t tmp = 0;
uint8_t red;
uint8_t green;
uint8_t blue;
if (bytes_per_pixel == 1) {
uint8_t offset = (x % pixels_per_byte) * self->bits_per_pixel;
uint8_t mask = (1 << self->bits_per_pixel) - 1;
return (pixel_data >> ((8 - self->bits_per_pixel) - offset)) & mask;
} else if (bytes_per_pixel == 2) {
if (self->g_bitmask == 0x07e0) { // 565
red = ((pixel_data & self->r_bitmask) >> 11);
green = ((pixel_data & self->g_bitmask) >> 5);
blue = ((pixel_data & self->b_bitmask) >> 0);
} else { // 555
red = ((pixel_data & self->r_bitmask) >> 10);
green = ((pixel_data & self->g_bitmask) >> 4);
blue = ((pixel_data & self->b_bitmask) >> 0);
}
tmp = (red << 19 | green << 10 | blue << 3);
return tmp;
} else if ((bytes_per_pixel == 4) && (self->bitfield_compressed)) {
return pixel_data & 0x00FFFFFF;
} else {
return pixel_data;
}
}
return 0;
}
uint16_t common_hal_displayio_ondiskbitmap_get_height(displayio_ondiskbitmap_t *self) {
return self->height;
}
uint16_t common_hal_displayio_ondiskbitmap_get_width(displayio_ondiskbitmap_t *self) {
return self->width;
}
mp_obj_t common_hal_displayio_ondiskbitmap_get_pixel_shader(displayio_ondiskbitmap_t *self) {
return MP_OBJ_FROM_PTR(self->pixel_shader_base);
}