canvas-heightmap

1.0.7 • Public • Published

canvas-heightmap

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Canvas Heightmap is a package to get images data by pixels, channels or average in different representations that can be used to build heightmaps.

Quick Start

Install

npm install canvas-heightmap

Use

const ch = new CanvasHeightmap();

// At first set the source and wait until it would be loaded.
ch.use('https://raw.githubusercontent.com/loginov-rocks/canvas-heightmap/master/test/resources/black-and-white.png').
    then(() => {
      // Secondly invoke draw method to render image to be able to get its data.
      ch.draw();
      // Eventually you can get needed data.
      const flatArray = ch.getFlatArray();
      const rgbaArray = ch.getRgbaArray();
    });

API

CanvasHeightmap

Canvas Heightmap class.

Kind: global class


new CanvasHeightmap()

Canvas Heightmap constructor.


use(source)Promise.<HTMLImageElement|HTMLCanvasElement>

Set canvas image source.

Kind: instance method of CanvasHeightmap

Parameter Type
source string | HTMLImageElement | HTMLCanvasElement

draw()HTMLCanvasElement

Draw image source on canvas.

Kind: instance method of CanvasHeightmap


getFlatArray([sx], [sy], [sw], [sh])Uint8ClampedArray

Get one-dimensional array containing the data in the RGBA order, with integer values between 0 and 255 (included).

Kind: instance method of CanvasHeightmap

See:

Parameter Type Default Description
[sx] number 0 The x coordinate of the upper left corner of the rectangle from which the data will be extracted.
[sy] number 0 The y coordinate of the upper left corner of the rectangle from which the data will be extracted.
[sw] number this._width The width of the rectangle from which the data will be extracted.
[sh] number this._height The height of the rectangle from which the data will be extracted.

getFlatAverageArray([sx], [sy], [sw], [sh])Uint8ClampedArray

Get one-dimensional array containing the data by pixels with average over RGB channels, with integer values between 0 and 255 (included).

Kind: instance method of CanvasHeightmap

Parameter Type Default Description
[sx] number 0 The x coordinate of the upper left corner of the rectangle from which the data will be extracted.
[sy] number 0 The y coordinate of the upper left corner of the rectangle from which the data will be extracted.
[sw] number this._width The width of the rectangle from which the data will be extracted.
[sh] number this._height The height of the rectangle from which the data will be extracted.

getFlatChannelArray(channel, [sx], [sy], [sw], [sh])Uint8ClampedArray

Get one-dimensional array containing the data for specified channel, with integer values between 0 and 255 (included).

Kind: instance method of CanvasHeightmap

Parameter Type Default Description
channel string Channel: red, green, blue or alpha.
[sx] number 0 The x coordinate of the upper left corner of the rectangle from which the data will be extracted.
[sy] number 0 The y coordinate of the upper left corner of the rectangle from which the data will be extracted.
[sw] number this._width The width of the rectangle from which the data will be extracted.
[sh] number this._height The height of the rectangle from which the data will be extracted.

getFlatRgbaArray([sx], [sy], [sw], [sh])Array.<Uint8ClampedArray>

Get two-dimensional array containing the data by pixels and RGBA array for each, with integer values between 0 and 255 (included).

Kind: instance method of CanvasHeightmap

Parameter Type Default Description
[sx] number 0 The x coordinate of the upper left corner of the rectangle from which the data will be extracted.
[sy] number 0 The y coordinate of the upper left corner of the rectangle from which the data will be extracted.
[sw] number this._width The width of the rectangle from which the data will be extracted.
[sh] number this._height The height of the rectangle from which the data will be extracted.

getAverageArray([sx], [sy], [sw], [sh])Array.<Uint8ClampedArray>

Get two-dimensional array containing the rows and cols data by pixels with average over RGB channels, with integer values between 0 and 255 (included).

Kind: instance method of CanvasHeightmap

Parameter Type Default Description
[sx] number 0 The x coordinate of the upper left corner of the rectangle from which the data will be extracted.
[sy] number 0 The y coordinate of the upper left corner of the rectangle from which the data will be extracted.
[sw] number this._width The width of the rectangle from which the data will be extracted.
[sh] number this._height The height of the rectangle from which the data will be extracted.

getChannelArray(channel, [sx], [sy], [sw], [sh])Array.<Uint8ClampedArray>

Get two-dimensional array containing the rows and cols data for specified channel, with integer values between 0 and 255 (included).

Kind: instance method of CanvasHeightmap

Parameter Type Default Description
channel string Channel: red, green, blue or alpha.
[sx] number 0 The x coordinate of the upper left corner of the rectangle from which the data will be extracted.
[sy] number 0 The y coordinate of the upper left corner of the rectangle from which the data will be extracted.
[sw] number this._width The width of the rectangle from which the data will be extracted.
[sh] number this._height The height of the rectangle from which the data will be extracted.

getRgbaArray([sx], [sy], [sw], [sh])Array.<Array.<Uint8ClampedArray>>

Get three-dimensional array containing the rows and cols data by pixels and RGBA array for each, with integer values between 0 and 255 (included).

Kind: instance method of CanvasHeightmap

Parameter Type Default Description
[sx] number 0 The x coordinate of the upper left corner of the rectangle from which the data will be extracted.
[sy] number 0 The y coordinate of the upper left corner of the rectangle from which the data will be extracted.
[sw] number this._width The width of the rectangle from which the data will be extracted.
[sh] number this._height The height of the rectangle from which the data will be extracted.

Package Sidebar

Install

npm i canvas-heightmap

Weekly Downloads

2

Version

1.0.7

License

MIT

Unpacked Size

79.9 kB

Total Files

19

Last publish

Collaborators

  • loginov-rocks