fltk.core.images

FLTK Images Library Bindings

This package provides low-level D bindings for the FLTK images library (libfltk_images), which adds support for loading various image formats.

Supported image formats:

  • BMP (Windows Bitmap)
  • GIF (Graphics Interchange Format)
  • JPEG (Joint Photographic Experts Group)
  • PNG (Portable Network Graphics)
  • PNM/PPM/PGM (Portable Anymap)
  • XBM (X BitMap)
  • XPM (X PixMap)

Memory Management:

  • Images created with *_new() functions must be destroyed with fltk_image_delete()
  • Shared images use reference counting via Fl_Shared_Image

Example: 

import fltk.core.images;

void main() {
   // Load a PNG image
   auto img = fltk_png_image_new("photo.png");
   if (img !is null) {
      auto w = fltk_image_w(fltk_png_image_as_image(img));
      auto h = fltk_image_h(fltk_png_image_as_image(img));
      writefln("Image size: %dx%d", w, h);
      fltk_png_image_delete(img);
   }
}

Authors

Dejan Lekić

License

BSD-3-Clause

Copyright

Copyright © 2025 DDN (D Developer Network) Members
alias FltkBitmap FltkBmpImage FltkGifImage FltkImage FltkJpegImage FltkPixmap FltkPngImage FltkPnmImage FltkRgbImage FltkSharedImage FltkTiledImage FltkXbmImage FltkXpmImage
enum FltkImageError
struct FltkBitmapHandle FltkBmpImageHandle FltkGifImageHandle FltkImageHandle FltkJpegImageHandle FltkPixmapHandle FltkPngImageHandle FltkPnmImageHandle FltkRgbImageHandle FltkSharedImageHandle FltkTiledImageHandle FltkXbmImageHandle FltkXpmImageHandle
fn fltk_bitmap_as_image fltk_bitmap_delete fltk_bitmap_new fltk_bmp_image_as_image fltk_bmp_image_delete fltk_bmp_image_fail fltk_bmp_image_new fltk_gif_image_as_image fltk_gif_image_delete fltk_gif_image_fail fltk_gif_image_new fltk_image_color_average fltk_image_copy fltk_image_count fltk_image_d fltk_image_data fltk_image_delete fltk_image_desaturate fltk_image_h fltk_image_inactive fltk_image_ld fltk_image_w fltk_jpeg_image_as_image fltk_jpeg_image_delete fltk_jpeg_image_fail fltk_jpeg_image_new fltk_jpeg_image_new_data fltk_pixmap_as_image fltk_pixmap_delete fltk_pixmap_new fltk_png_image_as_image fltk_png_image_delete fltk_png_image_fail fltk_png_image_new fltk_png_image_new_data fltk_pnm_image_as_image fltk_pnm_image_delete fltk_pnm_image_fail fltk_pnm_image_new fltk_rgb_image_as_image fltk_rgb_image_delete fltk_rgb_image_new fltk_shared_image_as_image fltk_shared_image_find fltk_shared_image_get fltk_shared_image_release fltk_tiled_image_as_image fltk_tiled_image_delete fltk_tiled_image_new fltk_xbm_image_as_image fltk_xbm_image_delete fltk_xbm_image_fail fltk_xbm_image_new fltk_xpm_image_as_image fltk_xpm_image_delete fltk_xpm_image_fail fltk_xpm_image_new isValid

Types 27

structFltkImageHandle

Opaque handle for Fl_Image base class.

This is the base type for all image handles.

Fields
private void * ptr
aliasFltkImage = FltkImageHandle *

Alias for image handle

structFltkRgbImageHandle

Opaque handle for Fl_RGB_Image.

RGB images store pixel data in RGB or RGBA format.

Fields
private void * ptr
aliasFltkRgbImage = FltkRgbImageHandle *

Alias for RGB image handle

structFltkBitmapHandle

Opaque handle for Fl_Bitmap.

Bitmaps are monochrome (1-bit) images.

Fields
private void * ptr
aliasFltkBitmap = FltkBitmapHandle *

Alias for bitmap handle

structFltkPixmapHandle

Opaque handle for Fl_Pixmap.

Pixmaps store images in XPM format.

Fields
private void * ptr
aliasFltkPixmap = FltkPixmapHandle *

Alias for pixmap handle

structFltkSharedImageHandle

Opaque handle for Fl_Shared_Image.

Shared images are reference-counted and cached.

Fields
private void * ptr
aliasFltkSharedImage = FltkSharedImageHandle *

Alias for shared image handle

structFltkBmpImageHandle

Opaque handle for Fl_BMP_Image.

Fields
private void * ptr
aliasFltkBmpImage = FltkBmpImageHandle *

Alias for BMP image handle

structFltkGifImageHandle

Opaque handle for Fl_GIF_Image.

Fields
private void * ptr
aliasFltkGifImage = FltkGifImageHandle *

Alias for GIF image handle

structFltkJpegImageHandle

Opaque handle for Fl_JPEG_Image.

Fields
private void * ptr
aliasFltkJpegImage = FltkJpegImageHandle *

Alias for JPEG image handle

structFltkPngImageHandle

Opaque handle for Fl_PNG_Image.

Fields
private void * ptr
aliasFltkPngImage = FltkPngImageHandle *

Alias for PNG image handle

structFltkPnmImageHandle

Opaque handle for Fl_PNM_Image.

Fields
private void * ptr
aliasFltkPnmImage = FltkPnmImageHandle *

Alias for PNM image handle

structFltkXbmImageHandle

Opaque handle for Fl_XBM_Image.

Fields
private void * ptr
aliasFltkXbmImage = FltkXbmImageHandle *

Alias for XBM image handle

structFltkXpmImageHandle

Opaque handle for Fl_XPM_Image.

Fields
private void * ptr
aliasFltkXpmImage = FltkXpmImageHandle *

Alias for XPM image handle

structFltkTiledImageHandle

Opaque handle for Fl_Tiled_Image.

Fields
private void * ptr
aliasFltkTiledImage = FltkTiledImageHandle *

Alias for tiled image handle

enumFltkImageError

Image loading error codes.

These values indicate the result of image loading operations.

OK = 0Image loaded successfully
FILE_NOT_FOUND = 1File not found or cannot be opened
INVALID_DATA = 2Invalid or corrupt image data
UNSUPPORTED_FORMAT = 3Unsupported image format
OUT_OF_MEMORY = 4Memory allocation failed

Functions 63

fnbool isValid(FltkImage image) @safe nothrow @nogcChecks if an image handle is valid (non-null).
fnbool isValid(FltkPngImage image) @safe nothrow @nogcChecks if a PNG image handle is valid (non-null).
fnbool isValid(FltkJpegImage image) @safe nothrow @nogcChecks if a JPEG image handle is valid (non-null).
fnbool isValid(FltkBmpImage image) @safe nothrow @nogcChecks if a BMP image handle is valid (non-null).
fnbool isValid(FltkGifImage image) @safe nothrow @nogcChecks if a GIF image handle is valid (non-null).
fnbool isValid(FltkSharedImage image) @safe nothrow @nogcChecks if a shared image handle is valid (non-null).
fnint fltk_image_w(FltkImage image)Gets the image width.
fnint fltk_image_h(FltkImage image)Gets the image height.
fnint fltk_image_d(FltkImage image)Gets the image depth (bytes per pixel).
fnint fltk_image_ld(FltkImage image)Gets the image line data size.
fnint fltk_image_count(FltkImage image)Gets the image data count.
fnconst(ubyte *) * fltk_image_data(FltkImage image)Gets a pointer to the image pixel data.
fnFltkImage fltk_image_copy(FltkImage image, int w, int h)Creates a copy of the image, optionally scaled.
fnvoid fltk_image_color_average(FltkImage image, uint color, float blend)Applies a color average to the image.
fnvoid fltk_image_inactive(FltkImage image)Creates an inactive (grayed) version of the image.
fnvoid fltk_image_desaturate(FltkImage image)Desaturates the image in place.
fnvoid fltk_image_delete(FltkImage image)Deletes an image.
fnFltkRgbImage fltk_rgb_image_new(const(ubyte) * data, int w, int h, int d, int ld)Creates a new RGB image from pixel data.
fnvoid fltk_rgb_image_delete(FltkRgbImage image)Deletes an RGB image.
fnFltkImage fltk_rgb_image_as_image(FltkRgbImage image)Casts an RGB image to base image.
fnFltkPngImage fltk_png_image_new(const(char) * filename)Creates a new PNG image from a file.
fnFltkPngImage fltk_png_image_new_data(const(ubyte) * data, int len)Creates a new PNG image from memory data.
fnvoid fltk_png_image_delete(FltkPngImage image)Deletes a PNG image.
fnFltkImage fltk_png_image_as_image(FltkPngImage image)Casts a PNG image to base image.
fnint fltk_png_image_fail(FltkPngImage image)Gets the error status of a PNG image load.
fnFltkJpegImage fltk_jpeg_image_new(const(char) * filename)Creates a new JPEG image from a file.
fnFltkJpegImage fltk_jpeg_image_new_data(const(ubyte) * data, int len)Creates a new JPEG image from memory data.
fnvoid fltk_jpeg_image_delete(FltkJpegImage image)Deletes a JPEG image.
fnFltkImage fltk_jpeg_image_as_image(FltkJpegImage image)Casts a JPEG image to base image.
fnint fltk_jpeg_image_fail(FltkJpegImage image)Gets the error status of a JPEG image load.
fnFltkBmpImage fltk_bmp_image_new(const(char) * filename)Creates a new BMP image from a file.
fnvoid fltk_bmp_image_delete(FltkBmpImage image)Deletes a BMP image.
fnFltkImage fltk_bmp_image_as_image(FltkBmpImage image)Casts a BMP image to base image.
fnint fltk_bmp_image_fail(FltkBmpImage image)Gets the error status of a BMP image load.
fnFltkPnmImage fltk_pnm_image_new(const(char) * filename)Creates a new PNM image from a file.
fnvoid fltk_pnm_image_delete(FltkPnmImage image)Deletes a PNM image.
fnFltkImage fltk_pnm_image_as_image(FltkPnmImage image)Casts a PNM image to base image.
fnint fltk_pnm_image_fail(FltkPnmImage image)Gets the error status of a PNM image load.
fnFltkGifImage fltk_gif_image_new(const(char) * filename)Creates a new GIF image from a file.
fnvoid fltk_gif_image_delete(FltkGifImage image)Deletes a GIF image.
fnFltkImage fltk_gif_image_as_image(FltkGifImage image)Casts a GIF image to base image.
fnint fltk_gif_image_fail(FltkGifImage image)Gets the error status of a GIF image load.
fnFltkBitmap fltk_bitmap_new(const(ubyte) * bits, int w, int h)Creates a new bitmap from XBM data.
fnvoid fltk_bitmap_delete(FltkBitmap bm)Deletes a bitmap.
fnFltkImage fltk_bitmap_as_image(FltkBitmap bm)Casts a bitmap to base image.
fnFltkPixmap fltk_pixmap_new(const(char *) * data)Creates a new pixmap from XPM data.
fnvoid fltk_pixmap_delete(FltkPixmap pm)Deletes a pixmap.
fnFltkImage fltk_pixmap_as_image(FltkPixmap pm)Casts a pixmap to base image.
fnFltkXbmImage fltk_xbm_image_new(const(char) * filename)Creates an XBM image from a file.
fnvoid fltk_xbm_image_delete(FltkXbmImage img)Deletes an XBM image.
fnFltkImage fltk_xbm_image_as_image(FltkXbmImage img)Casts an XBM image to base image.
fnint fltk_xbm_image_fail(FltkXbmImage img)Gets the error status of an XBM image load.
fnFltkXpmImage fltk_xpm_image_new(const(char) * filename)Creates an XPM image from a file.
fnvoid fltk_xpm_image_delete(FltkXpmImage img)Deletes an XPM image.
fnFltkImage fltk_xpm_image_as_image(FltkXpmImage img)Casts an XPM image to base image.
fnint fltk_xpm_image_fail(FltkXpmImage img)Gets the error status of an XPM image load.
fnFltkTiledImage fltk_tiled_image_new(FltkImage image, int w, int h)Creates a new tiled image from a source image.
fnvoid fltk_tiled_image_delete(FltkTiledImage ti)Deletes a tiled image.
fnFltkImage fltk_tiled_image_as_image(FltkTiledImage ti)Casts a tiled image to base image.
fnFltkSharedImage fltk_shared_image_get(const(char) * filename)Gets a shared image from file (loads if not cached).
fnFltkSharedImage fltk_shared_image_find(const(char) * filename)Finds a shared image in the cache.
fnvoid fltk_shared_image_release(FltkSharedImage image)Releases a reference to a shared image.
fnFltkImage fltk_shared_image_as_image(FltkSharedImage image)Casts a shared image to base image.