bmp-loader

Github Repo	C Header	C source	JS source
mongoose-os-libs/bmp-loader	mgos_bmp_loader.h		api_bmp.js

This is a Mongoose OS library to use "libbmpread" by Charles Lindsay "chazomaticus" seamlessly in Mongoose OS applications.

The third-party software is integrated without modification under the directory third_party. The documentation for the underlying lib can also be found in the third_party directory. The external library is 100% original and not changed (will be included as submodule in a future version), so it's easier to integrate updates later, if they show up.

Be aware: this library might be subject of change, so use it at your own risk!

Dependencies

This library has a dependency:

• libbmpread

Documentation

These functions are available via C calls:

   // create the needed structure to hold the data:
   bmpread_t* mgos_bmp_loader_create(void)
   
   // load an BMP image
   bool mgos_bmp_loader_load(bmpread_t* p_bmp, const char* bmp_file, unsigned int flags)

   // free the allocated space
   void mgos_bmp_loader_free(bmpread_t* p_bmp)

   // get the plain data pointer of the image
   uint8_t* mgos_bmp_loader_get_data(bmpread_t* p_bmp)

   // get the width and height of the image (wrappers for FFI)
   uint32_t mgos_bmp_loader_get_width(bmpread_t* p_bmp)
   uint32_t mgos_bmp_loader_get_height(bmpread_t* p_bmp)

   // rotate the image in 90° steps
   bool mgos_bmp_loader_rotate(bmpread_t* p_bmp, uint16_t angle)

A MJS API is included as well:

Include the API with

load('api_bmp.js');

in your own MJS file like ìnit.js.

These functions are available as MJS API calls:

   // the object containing the API
   let BMP_LOADER = { ... };

   // create a new object with the needed structure
   create: function () { ... }
   
   // load a BMP file
   load: function (file, flags)  { ... }
   
   // free the underlying structure and the bitmap data
   free: function () { ... }
   
   // get a pointer to the raw bitmap data
   getData: function () { ... }
   
   // get a certain pixel of the bitmap as pointer to the bytes
   getPixel: function (x, y) { ... }
   
   // get the width of the image
   getWidth: function () { ... }
   
   // get the height of the image
   getHeight: function () {...}

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JS API

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bitmap.getPixel

bitmap.getPixel(x, y)

Returns pixel's RGB value at pos x,y

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