1.canvas draw橢圓 通過
scale
2.arc 前必須beginPath
2.arc 前必須beginPath
canvas_context.save();
canvas_context.scale(1, _scale);
canvas_context.beginPath();
canvas_context.arc(_centerX, _centerY, parseInt(_bounds[2] * 0.5), 0,(Math.PI/180)*360, true);
canvas_context.restore();
canvas_context.scale(1, _scale);
canvas_context.beginPath();
canvas_context.arc(_centerX, _centerY, parseInt(_bounds[2] * 0.5), 0,(Math.PI/180)*360, true);
canvas_context.restore();