function recompute()

in seriously.js [5820:5907]

• 63 lines of code
• 14 McCabe index (conditional complexity)

		function recompute() {
			var matrix = me.matrix,
				angle,
				s, c,
				m00,
				m01,
				m02,
				m03,
				m10,
				m11,
				m12,
				m13;

			function translate(x, y) {
				matrix[12] = matrix[0] * x + matrix[4] * y + matrix[12];
				matrix[13] = matrix[1] * x + matrix[5] * y + matrix[13];
				matrix[14] = matrix[2] * x + matrix[6] * y + matrix[14];
				matrix[15] = matrix[3] * x + matrix[7] * y + matrix[15];
			}

			if (!translateX &&
					!translateY &&
					!rotation &&
					!skewX &&
					!skewY &&
					scaleX === 1 &&
					scaleY === 1
					) {
				me.transformed = false;
				return;
			}

			//calculate transformation matrix
			mat4.identity(matrix);

			translate(translateX + centerX, translateY + centerY);

			//skew
			if (skewX) {
				matrix[4] = skewX / me.width;
			}
			if (skewY) {
				matrix[1] = skewY / me.height;
			}

			if (rotation) {
				m00 = matrix[0];
				m01 = matrix[1];
				m02 = matrix[2];
				m03 = matrix[3];
				m10 = matrix[4];
				m11 = matrix[5];
				m12 = matrix[6];
				m13 = matrix[7];

				//rotate
				angle = -(degrees ? rotation * Math.PI / 180 : rotation);
				//...rotate
				s = Math.sin(angle);
				c = Math.cos(angle);
				matrix[0] = m00 * c + m10 * s;
				matrix[1] = m01 * c + m11 * s;
				matrix[2] = m02 * c + m12 * s;
				matrix[3] = m03 * c + m13 * s;
				matrix[4] = m10 * c - m00 * s;
				matrix[5] = m11 * c - m01 * s;
				matrix[6] = m12 * c - m02 * s;
				matrix[7] = m13 * c - m03 * s;
			}

			//scale
			if (scaleX !== 1) {
				matrix[0] *= scaleX;
				matrix[1] *= scaleX;
				matrix[2] *= scaleX;
				matrix[3] *= scaleX;
			}
			if (scaleY !== 1) {
				matrix[4] *= scaleY;
				matrix[5] *= scaleY;
				matrix[6] *= scaleY;
				matrix[7] *= scaleY;
			}

			translate(-centerX, -centerY);

			me.transformed = true;
		}