screenshot: image capture: support insets on client frame

The insets include the native client border, which results in an 8px
alpha border on the image. Remove the insets from the screenshot.

With j2d scaling the image size is an extra pixel wide and the client
position within the frame is an extra pixel down (with gpu). I think
this is due to the rounding of getScaledValue(), which was originally
copied from jogl.

runelite-client/src/main/java/net/runelite/client/plugins/gpu/GpuPlugin.java

@@ -1847,7 +1847,7 @@ private GpuIntBuffer bufferForTriangles(int triangles)
 
 	private int getScaledValue(final double scale, final int value)
 	{
-		return (int) (value * scale + .5);
+		return (int) (value * scale);
 	}
 
 	private void glDpiAwareViewport(final int x, final int y, final int width, final int height)

runelite-client/src/main/java/net/runelite/client/ui/ClientUI.java

@@ -47,6 +47,7 @@
 import java.awt.Image;
 import java.awt.Insets;
 import java.awt.LayoutManager2;
+import java.awt.Point;
 import java.awt.Rectangle;
 import java.awt.SystemTray;
 import java.awt.Taskbar;
@@ -94,7 +95,6 @@
 import net.runelite.api.Constants;
 import net.runelite.api.GameState;
 import net.runelite.api.Player;
-import net.runelite.api.Point;
 import net.runelite.api.events.GameStateChanged;
 import net.runelite.api.widgets.ComponentID;
 import net.runelite.api.widgets.Widget;
@@ -875,7 +875,7 @@ public void setCursor(final BufferedImage image, final String name)
 			return;
 		}
 
-		final java.awt.Point hotspot = new java.awt.Point(0, 0);
+		final Point hotspot = new Point(0, 0);
 		final Cursor cursorAwt = Toolkit.getDefaultToolkit().createCustomCursor(image, hotspot, name);
 		defaultCursor = cursorAwt;
 		setCursor(cursorAwt);
@@ -917,14 +917,18 @@ public Point getCanvasOffset()
 			final Canvas canvas = ((Client) client).getCanvas();
 			if (canvas != null)
 			{
-				final java.awt.Point point = SwingUtilities.convertPoint(canvas, 0, 0, frame);
-				return new Point(point.x, point.y);
+				return SwingUtilities.convertPoint(canvas, 0, 0, frame);
 			}
 		}
 
 		return new Point(0, 0);
 	}
 
+	public Insets getInsets()
+	{
+		return frame.getInsets();
+	}
+
 	/**
 	 * Paint UI related overlays to target graphics
 	 * @param graphics target graphics

runelite-client/src/main/java/net/runelite/client/util/ImageCapture.java

@@ -28,6 +28,8 @@
 import com.google.common.base.Strings;
 import java.awt.Graphics2D;
 import java.awt.Image;
+import java.awt.Insets;
+import java.awt.Point;
 import java.awt.Toolkit;
 import java.awt.TrayIcon;
 import java.awt.datatransfer.Clipboard;
@@ -49,7 +51,6 @@
 import lombok.extern.slf4j.Slf4j;
 import net.runelite.api.Client;
 import net.runelite.api.GameState;
-import net.runelite.api.Point;
 import net.runelite.client.Notifier;
 import static net.runelite.client.RuneLite.SCREENSHOT_DIR;
 import net.runelite.client.config.RuneScapeProfileType;
@@ -115,11 +116,15 @@ public BufferedImage addClientFrame(Image image)
 		final AffineTransform transform = OSType.getOSType() == OSType.MacOS ? new AffineTransform() :
 			clientUi.getGraphicsConfiguration().getDefaultTransform();
 
+		// on Windows the insets are the window border
+		Insets insets = clientUi.getInsets();
+		transform.translate(-insets.left, -insets.top);
+
 		// scaled client dimensions
-		int clientWidth = getScaledValue(transform.getScaleX(), clientUi.getWidth());
-		int clientHeight = getScaledValue(transform.getScaleY(), clientUi.getHeight());
+		int screenshotWidth = getScaledValue(transform.getScaleX(), clientUi.getWidth() - insets.left - insets.right);
+		int screenshotHeight = getScaledValue(transform.getScaleY(), clientUi.getHeight() - insets.top - insets.bottom);
 
-		final BufferedImage screenshot = new BufferedImage(clientWidth, clientHeight, BufferedImage.TYPE_INT_ARGB);
+		final BufferedImage screenshot = new BufferedImage(screenshotWidth, screenshotHeight, BufferedImage.TYPE_INT_ARGB);
 
 		Graphics2D graphics = (Graphics2D) screenshot.getGraphics();
 		AffineTransform originalTransform = graphics.getTransform();
@@ -138,8 +143,11 @@ public BufferedImage addClientFrame(Image image)
 
 		// Find the position of the canvas inside the frame
 		final Point canvasOffset = clientUi.getCanvasOffset();
-		final int gameOffsetX = getScaledValue(transform.getScaleX(), canvasOffset.getX());
-		final int gameOffsetY = getScaledValue(transform.getScaleY(), canvasOffset.getY());
+		canvasOffset.x -= insets.left;
+		canvasOffset.y -= insets.top;
+
+		final int gameOffsetX = getScaledValue(transform.getScaleX(), (int) canvasOffset.getX());
+		final int gameOffsetY = getScaledValue(transform.getScaleY(), (int) canvasOffset.getY());
 
 		// Draw the original screenshot onto the new screenshot
 		graphics.setTransform(originalTransform); // the original screenshot is already scaled
@@ -151,7 +159,7 @@ public BufferedImage addClientFrame(Image image)
 
 	private static int getScaledValue(final double scale, final int value)
 	{
-		return (int) (value * scale + .5);
+		return (int) (value * scale);
 	}
 
 	/**