This is a part of Node3D project.
npm i image-raub
Node.js N-API addon implementing the HTMLImageElement.
Note: this addon uses N-API, and therefore is ABI-compatible across different Node.js versions. Addon binaries are precompiled and there is no compilation step during the
npm i
command.
The src
property can be:
- A local file.
- A data URI.
- A http(s) URL.
FreeImage is used as backend decoder.
Additional features include:
- Save the image to disk.
- Create an Image from raw RGBA pixel data.
- Some context 2d functionality, e.g.
drawImage
.
const Image = require('image-raub');
const image = new Image();
// Web-style onload
image.onload = () => {
gl.pixelStorei(gl.UNPACK_FLIP_Y_WEBGL, true);
gl.bindTexture(gl.TEXTURE_2D, texture);
gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, image);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR_MIPMAP_NEAREST);
gl.generateMipmap(gl.TEXTURE_2D);
gl.bindTexture(gl.TEXTURE_2D, null);
};
image.src = `${__dirname}/texture.jpg`;
Here Image
is used to load a texture. The constructed object receives src
property,
then the file is read and 'load'
event is emitted. After that, image.data
is
available as a Buffer
, containing the whole pixel data, and image.width
/image.height
contain the dimensions.
const memSize = screen.w * screen.h * 4; // estimated number of bytes
const storage = { data: Buffer.allocUnsafeSlow(memSize) };
gl.readPixels(
0, 0,
screen.w, screen.h,
gl.RGBA,
gl.UNSIGNED_BYTE,
storage
);
const img = Image.fromPixels(screen.w, screen.h, 32, storage.data);
img.save(`${Date.now()}.jpg`);
Image can save its current content to the filesystem. It can also load from raw
pixel values using static fromPixels()
method.
get/set number width/naturalWidth
- image width.get/set number height/naturalHeight
- image height.get/set [width, height] wh
- image width and height.get/set {width, height} size
- image width and height.get/set string src
- image source file.get/set function onload
- setter uses.on('load', ...)
method, getter returns all listeners.get/set function onerror
- setter uses.on('error', ...)
method, getter returns all listeners.get boolean complete
- if image has already been loaded.
save(string dest)
- save Image to file. Resize tow, h
is optional.drawImage(src, ...)
- refer to drawImage, but optional paramsdx, dy
are ignored.load(Buffer data)
- load from a file in memory.static fromPixels(uint width, uint height, uint bpp, Buffer pixels)
- create image from raw pixels. For example it helps when you want to store the result ofglReadPixels()
as an image.
'load'
- the requested (src
) file was loaded.'error'
- an error has occured.