chatdraw text

//get chatdraw [r,g,b] palette
function getColors() {
    var colorButtons = document.querySelectorAll("#chatdraw>button-area>button.colorChange");
    var colors = new Array(colorButtons.length);
    for (var i = 0; i < colorButtons.length; i++) {
        var color = StyleUtilities.GetColor(colorButtons[i].style.color);
        //console.log(color)
        colors[i] = [color.r, color.g, color.b];
    }
    return colors
}

//apply [r,g,b] palette to image data
function palettize(imageData,palette){
    var bestIndex;
    for (var x = 0; x < imageData.data.length; x += 4) {
        var bestDist = Infinity;
        for (var i = 0; i < palette.length && bestDist !== 0; i++) {
            for (var j = 0, dist = 0, color = palette[i]; j < 3; j++)
                dist += Math.abs(imageData.data[x + j] - color[j]) * [3, 6, 1][j];
            if (dist < bestDist) {
                bestDist = dist;
                bestIndex = i;
            }
        }
        for (i = 0; i < 3; i++)
            imageData.data[x + i] = palette[bestIndex][i];
    }
    return imageData;
}

//tool
var textTool = new CanvasDrawerTool(function (data, context) {
    if (data.action & CursorActions.End && data.onTarget) {
        context.font = data.lineWidth * 5 + 6 + "px Comic Sans MS"; //what a great way to set font size
        context.textBaseline = "top"; //somebody forgot where the origin is
        var text = prompt();
        if (text === null) return;
        context.fillText(text, data.x, data.y);

        context.putImageData(palettize(context.getImageData(0, 0, context.canvas.width, context.canvas.height),getColors()), 0, 0);
    }
})

LocalChatDraw.getDrawer().tools["textTool"] = textTool;
var button = LocalChatDraw.createToolButton("T", "textTool");
var buttonArea = document.querySelectorAll("#chatdraw button-area")[1];
buttonArea.insertBefore(button, buttonArea.firstChild);