view fft/cross/FFT.js @ 15:ece8682d8293

Avoid generating browser/filesystem support with Emscripten (not needed)

"use strict";

var crossModule = CrossModule({});

var fftCross = crossModule.cwrap(
    'fftCross', 'void', ['number', 'number', 'number',
			 'number', 'number', 'number' ]
);

function FFTCross(size) {
    this.size = size;
    this.n = size * 8;
    this.ptr = crossModule._malloc(this.n * 4);
    this.ri = new Uint8Array(crossModule.HEAPU8.buffer, this.ptr, this.n);
    this.ii = new Uint8Array(crossModule.HEAPU8.buffer, this.ptr + this.n, this.n);
    this.transform = function(real, imag, inverse) {
	var ptr = this.ptr;
	var n = this.n;
	this.ri.set(new Uint8Array(real.buffer));
	this.ii.set(new Uint8Array(imag.buffer));
	fftCross(this.size, inverse,
		 ptr, ptr + n, ptr + n * 2, ptr + n * 3);
	var ro = new Float64Array(crossModule.HEAPU8.buffer, ptr + n * 2, this.size);
	var io = new Float64Array(crossModule.HEAPU8.buffer, ptr + n * 3, this.size);
	return { real: ro, imag: io };
    }
    this.transformReal = function(real, inverse) {
	var ptr = this.ptr;
	var n = this.n;
	this.ri.set(new Uint8Array(real.buffer));
	fftCross(this.size, inverse,
		 ptr, 0, ptr + n * 2, ptr + n * 3);
	var ro = new Float64Array(crossModule.HEAPU8.buffer, ptr + n * 2, this.size);
	var io = new Float64Array(crossModule.HEAPU8.buffer, ptr + n * 3, this.size);
	return { real: ro, imag: io };
    }
    this.discard = function() {
	crossModule._free(this.ptr);
    }
}