Stop assuming that our render pipeline will only process RGB frames

For one, we have already switched to RGBA some time ago, so the name was
technically incorrect already.
But the main reason is that we'll want to use them for depth maps as well (and
potentially maybe even for HDR images if that's possible with canvas?).

src/main/java/com/replaymod/render/utils/Utils.java

@@ -1,24 +1,41 @@
 package com.replaymod.render.utils;
 
+import com.replaymod.render.frame.OpenGlFrame;
+
 import java.nio.ByteBuffer;
 
 public class Utils {
     /**
      * Copies the rgb image (flipped vertically) to the specified position in the target buffer
-     * @param buffer Source image
-     * @param bufferWidth  Source image width
+     * @param source Source image
      * @param xOffset X offset in target image
      * @param yOffset Y offset in target image
      * @param to Target image
      * @param width Target image width
      */
-    public static void openGlBytesToRBG(ByteBuffer buffer, int bufferWidth, int xOffset, int yOffset, ByteBuffer to, int width) {
-        byte[] rowBuf = new byte[bufferWidth * 4];
+    public static void openGlBytesToBitmap(OpenGlFrame source, int xOffset, int yOffset, ByteBuffer to, int width) {
+        openGlBytesToBitmap(
+                source.getByteBuffer(), source.getSize().getWidth(), source.getBytesPerPixel(),
+                xOffset, yOffset, to, width);
+    }
+
+    /**
+     * Copies the rgb image (flipped vertically) to the specified position in the target buffer
+     * @param buffer Source image
+     * @param bufferWidth  Source image width
+     * @param bbp Bytes per pixel
+     * @param xOffset X offset in target image
+     * @param yOffset Y offset in target image
+     * @param to Target image
+     * @param width Target image width
+     */
+    public static void openGlBytesToBitmap(ByteBuffer buffer, int bufferWidth, int bbp, int xOffset, int yOffset, ByteBuffer to, int width) {
+        byte[] rowBuf = new byte[bufferWidth * bbp];
         // Copy image flipped vertically to target buffer
-        int rows = buffer.remaining() / 4 / bufferWidth;
+        int rows = buffer.remaining() / bbp / bufferWidth;
         for (int i = 0; i < rows; i++) {
             buffer.get(rowBuf);
-            to.position(((yOffset + rows - i - 1) * width + xOffset) * 4);
+            to.position(((yOffset + rows - i - 1) * width + xOffset) * bbp);
             to.put(rowBuf);
         }
         to.rewind();