import Exception from './Exception' ; import InvertedLuminanceSource from './InvertedLuminanceSource' ; import StringBuilder from './util/StringBuilder' ; author dswitkin google abstract class LuminanceSource { protected constructor ( private width , private height ) { } param y param row return public abstract getRow ( y , row ? ) ; return public abstract getMatrix ( ) ; return public getWidth ( ) { return this . width ; } return public getHeight ( ) { return this . height ; } return public isCropSupported ( ) { return false ; } param left param top param width param height return public crop ( left , top , width , height ) { throw new Exception ( Exception . UnsupportedOperationException , "This luminance source does not support cropping." ) ; } return public isRotateSupported ( ) { return false ; } return public abstract invert ( ) ; /**
     * Returns a new object with rotated image data by 90 degrees counterclockwise.
     * Only callable if  {@link #isRotateSupported()} is true.
     *
     *  return public rotateCounterClockwise ( ) { throw new Exception ( Exception . UnsupportedOperationException , "This luminance source does not support rotation by 90 degrees." ) ; } /**
     * Returns a new object with rotated image data by 45 degrees counterclockwise.
     * Only callable if  {@link #isRotateSupported()} is true.
     *
     *  return public rotateCounterClockwise45 ( ) { throw new Exception ( Exception . UnsupportedOperationException , "This luminance source does not support rotation by 45 degrees." ) ; } public toString ( ) { const row = new Uint8ClampedArray ( this . width ) ; let result = new StringBuilder ( ) ; for ( let y = 0 ; y < this . height ; y ++ ) { const sourceRow = this . getRow ( y , row ) ; for ( let x = 0 ; x < this . width ; x ++ ) { const luminance = sourceRow [ x ] & 0xFF ; let c ; if ( luminance < 0x40 ) { c = '#' ; } else if ( luminance < 0x80 ) { c = '+' ; } else if ( luminance < 0xC0 ) { c = '.' ; } else { c = ' ' ; } result . append ( c ) ; } result . append ( '\n' ) ; } return result . toString ( ) ; } } export default LuminanceSource ;