protected void drawCurve()

in application/org.openjdk.jmc.flightrecorder.ext.g1/src/main/java/org/openjdk/jmc/flightrecorder/ext/g1/visualizer/HeapLayout.java [268:367]
100 lines of code
24 McCabe index (conditional complexity)

	protected void drawCurve(GC gc) {
		int n = closestLargerPowerOfTwo((int) Math.round(Math.sqrt(regions.size())));
		int scaleY = Math.floorDiv(getClientArea().height, n);
		int scaleX = Math.floorDiv(getClientArea().width, n);
		int i = 0, j = 0, size = 0;
		try {
			size = Math.floorDiv(getClientArea().width, scaleX);
		} catch (ArithmeticException ae) {
			return;
		}
		Rectangle last = new Rectangle(0, 0, 0, 0);
		boolean first = true, flip = false;
		if (dirtyRegions.size() == 0 && scaleY == scalingFactorY && scaleX == scalingFactorX && !fullRedraw) {
			gc.setBackground(Display.getCurrent().getSystemColor(SWT.COLOR_WHITE));
			GC gc2 = new GC(lastDraw);
			updateFocus(gc2);
			gc2.dispose();
			gc.drawImage(lastDraw, 0, 0);
		} else if (dirtyRegions.size() > 0 && !fullRedraw) {
			GC buffer = new GC(lastDraw);
			for (HeapRegion region : dirtyRegions) {
				buffer.setBackground(colors.getColor(region));
				buffer.fillRectangle(region.getPosition());
				drawPad(buffer, region.getPosition());
			}
			updateFocus(buffer);
			gc.drawImage(lastDraw, 0, 0);
			buffer.dispose();
			dirtyRegions.clear();
		} else if (regions.size() == 0) {
			gc.setBackground(getDisplay().getSystemColor(SWT.COLOR_WHITE));
			gc.fillRectangle(this.getClientArea());
		} else {
			scalingFactorY = (scaleY == 0) ? 1 : scaleY;
			scalingFactorX = (scaleX == 0) ? 1 : scaleX;
			Rectangle fullSize = new Rectangle(0, 0, 0, 0);
			for (HeapRegion region : regions) {
				Rectangle pos = new Rectangle(0, 0, scalingFactorX, scalingFactorY);
				switch (curveType) {
				case HILBERT:
					Point hilbert = convertTo2D(n, i);
					pos = new Rectangle(hilbert.x * scalingFactorX, hilbert.y * scalingFactorY, scalingFactorX,
							scalingFactorY);
					break;
				case LEFT_RIGHT:
					if (j < size && !first) {
						pos.x = last.x + scaleX;
						pos.y = last.y;
						j++;
					} else if (first) {
						pos.x = 0;
						pos.y = 0;
						j++;
						first = false;
					} else {
						j = 1;
						pos.x = 0;
						pos.y = last.y + scaleY;
					}
					last = pos;
					break;
				case ALTERNATING:
					if (j < size && !first) {
						pos.x = flip ? last.x - scaleX : last.x + scaleX;
						pos.y = last.y;
						j++;
					} else if (first) {
						pos.x = 0;
						pos.y = 0;
						++j;
						first = false;
					} else {
						j = 1;
						pos.x = last.x;
						pos.y = last.y + scaleY;
						flip = !flip;
					}
					last = pos;
					break;
				}
				region.setPosition(pos);
				fullSize.add(pos);
				i++;
			}
			Image current = new Image(getDisplay(), fullSize);
			GC buffer = new GC(current);
			for (HeapRegion region : regions) {
				buffer.setBackground(colors.getColor(region));
				buffer.fillRectangle(region.getPosition());
				drawPad(buffer, region.getPosition());
			}
			gc.drawImage(current, 0, 0);
			updateFocus(buffer);
			this.setBounds(current.getBounds());
			this.getParent().layout(true, true);
			buffer.dispose();
			lastDraw = current;
			fullRedraw = false;
		}
	}