Moving global variables to prototype scope

[zagibu]

I'd like to move the global variables vertexBlaBuffer to the scope of the Geometry prototype:

function Geometry(position, rotation, path) {
	this.position = position;
	this.rotation = rotation;
	this.path = path;

	var request = new XMLHttpRequest();
	request.open("GET", path);
	request.onreadystatechange = function() {
		if (request.readyState == 4) {
			handleLoadedModel(JSON.parse(request.responseText));
		}
	}
	request.send();

	initTextures();
}

var vertexPositionBuffer;
var vertexNormalBuffer;
var vertexTextureCoordBuffer;
var vertexIndexBuffer;
function handleLoadedModel(modelData) {
	vertexNormalBuffer = gl.createBuffer();
	gl.bindBuffer(gl.ARRAY_BUFFER, vertexNormalBuffer);
	gl.bufferData(gl.ARRAY_BUFFER, new WebGLFloatArray(modelData.vertexNormals), gl.STATIC_DRAW);
	vertexNormalBuffer.itemSize = 3;
	vertexNormalBuffer.numItems = modelData.vertexNormals.length / 3;

	vertexTextureCoordBuffer = gl.createBuffer();
	gl.bindBuffer(gl.ARRAY_BUFFER, vertexTextureCoordBuffer);
	gl.bufferData(gl.ARRAY_BUFFER, new WebGLFloatArray(modelData.vertexTextureCoords), gl.STATIC_DRAW);
	vertexTextureCoordBuffer.itemSize = 2;
	vertexTextureCoordBuffer.numItems = modelData.vertexTextureCoords.length / 2;

	vertexPositionBuffer = gl.createBuffer();
	gl.bindBuffer(gl.ARRAY_BUFFER, vertexPositionBuffer);
	gl.bufferData(gl.ARRAY_BUFFER, new WebGLFloatArray(modelData.vertexPositions), gl.STATIC_DRAW);
	vertexPositionBuffer.itemSize = 3;
	vertexPositionBuffer.numItems = modelData.vertexPositions.length / 3;

	vertexIndexBuffer = gl.createBuffer();
	gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, vertexIndexBuffer);
	gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, new WebGLUnsignedShortArray(modelData.indices), gl.STREAM_DRAW);
	vertexIndexBuffer.itemSize = 1;
	vertexIndexBuffer.numItems = modelData.indices.length;
}

Geometry.prototype.draw = function() {
	mvPushMatrix();
	mvTranslate(this.position);
	multMatrix(this.rotation);

	// Tell WebGL you want to work with the cube's vertex positions buffer
	gl.bindBuffer(gl.ARRAY_BUFFER, this.vertexPositionBuffer);
    // Feed the shader program with the cube's vertex positions
	gl.vertexAttribPointer(currentProgram.vertexPositionAttribute,
		this.vertexPositionBuffer.itemSize, gl.FLOAT, false, 0, 0);

	// Tell WebGL you want to work with the cube's normal buffer
	gl.bindBuffer(gl.ARRAY_BUFFER, this.vertexNormalBuffer);
	// Feed the shader program with the cube's vertex normals
	gl.vertexAttribPointer(currentProgram.vertexNormalAttribute,
		this.vertexNormalBuffer.itemSize, gl.FLOAT, false, 0, 0);

	// Tell WebGL you want to work with the cube's texture buffer
	gl.bindBuffer(gl.ARRAY_BUFFER, this.vertexTextureCoordBuffer);
	// Feed the shader program with the cube's texture data
	gl.vertexAttribPointer(currentProgram.textureCoordAttribute,
		this.vertexTextureCoordBuffer.itemSize, gl.FLOAT, false, 0, 0);

	gl.activeTexture(gl.TEXTURE0);
	gl.bindTexture(gl.TEXTURE_2D, texture);
	gl.uniform1i(currentProgram.samplerUniform, 0);

	// Tell WebGL you want to work with the cube's vertex index buffer
	gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, this.vertexIndexBuffer);

		// Draw the cube
	gl.drawElements(gl.TRIANGLES, this.vertexIndexBuffer.numItems,
		gl.UNSIGNED_SHORT, 0);

	mvPopMatrix();
}

Any tips?

[zagibu]

I've managed to do it by saving the this reference in a var, which is accessible within the anonymous function.