Show BMP image on display

Question

Hi there! 
 I have an SD card reader and ST7735 connected to an nRF52850 DK, both working fine. Furthermore, I 'm using ARMGCC in combination with Make, nRF5 SDK, nRF SDK for Mesh, FreeRTOS and C++. Now I've got the following question; how do I show bitmaps on the display that're stored on the sd card? 
 I couldn't find any examples that do so and I've actually wasted quite a lot of time on it by writing it pixel by pixel... Has anyone accomplished this, or does anyone have an idea how this could be tackled? 
 Kind regards, 
 Jochem

JVKran · Accepted Answer

Hi Simon, Thanks for pointing that out! Got that working almost instantly. That topic, however, doesn't really provide any information with regards to writing an image from the SD card to a display. Since I couldn't get the function form the GFX library working, I decided to write my own that takes the filename and rectangle as input. ret_code_t display_c::show_image(nrf_gfx_rect_t const * p_rect, const char* file_name){ UINT bytes_read; FIL f; if(f_open(&f, file_name, FA_READ) != FR_OK){ NRF_LOG_WARNING("Opening \"%s\" failed.", file_name); return NRF_ERROR_NOT_FOUND; } if ((p_rect->x > nrf_gfx_width_get(&lcd)) || (p_rect->y > nrf_gfx_height_get(&lcd))){ return NRF_ERROR_INVALID_PARAM; } uint16_t signature; f_read(&f, &signature, 2, &bytes_read); uint32_t size, creator_bytes, image_offset; f_read(&f, &size, 4, &bytes_read); f_read(&f, &creator_bytes, 4, &bytes_read); f_read(&f, &image_offset, 4, &bytes_read); f_lseek(&f, image_offset); uint16_t pixel; for (int32_t i = 0; i < p_rect->height; i++){ for (uint32_t j = 0; j < p_rect->width; j++){ f_read(&f, &pixel, 2, &bytes_read); lcd.lcd_pixel_draw(p_rect->x + j, p_rect->y + i, pixel); } } f_close(&f); NRF_LOG_WARNING("Image \"%s\" drawn.", file_name); return NRF_SUCCESS; } For anyone facing the same challenge; feel free to use it. Kind regards, Jochem

Show BMP image on display

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