PaperMC/patches/server/1064-Reduce-work-done-in-CraftMapCanvas.drawImage-by-limi.patch
2024-11-11 18:04:22 +01:00

75 lines
3.7 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Barnaby <22575741+barnabwhy@users.noreply.github.com>
Date: Sat, 29 Jun 2024 12:06:51 +0100
Subject: [PATCH] Reduce work done in CraftMapCanvas.drawImage by limiting size
of image and using System.arraycopy instead of for loops and use bitwise
operations to do bounds checks.
diff --git a/src/main/java/org/bukkit/craftbukkit/map/CraftMapCanvas.java b/src/main/java/org/bukkit/craftbukkit/map/CraftMapCanvas.java
index ff59f759669620795ef355c988b664bdcda39f52..a5e98571d6d83390761c11e28a0bc3c4415799cd 100644
--- a/src/main/java/org/bukkit/craftbukkit/map/CraftMapCanvas.java
+++ b/src/main/java/org/bukkit/craftbukkit/map/CraftMapCanvas.java
@@ -91,12 +91,41 @@ public class CraftMapCanvas implements MapCanvas {
@Override
public void drawImage(int x, int y, Image image) {
- byte[] bytes = MapPalette.imageToBytes(image);
- for (int x2 = 0; x2 < image.getWidth(null); ++x2) {
- for (int y2 = 0; y2 < image.getHeight(null); ++y2) {
- this.setPixel(x + x2, y + y2, bytes[y2 * image.getWidth(null) + x2]);
+ // Paper start - Reduce work done by limiting size of image and using System.arraycopy
+ int width = 128 - x;
+ int height = 128 - y;
+ if (image.getHeight(null) < height)
+ height = image.getHeight(null);
+
+ // Create a subimage if the image is larger than the max allowed size
+ java.awt.image.BufferedImage temp;
+ if (image.getWidth(null) >= width && image instanceof java.awt.image.BufferedImage bImage) {
+ // If the image is larger than the max allowed size, get a subimage, otherwise use the image as is
+ if (image.getWidth(null) > width || image.getHeight(null) > height) {
+ temp = bImage.getSubimage(0, 0, width, height);
+ } else {
+ temp = bImage;
}
+ } else {
+ temp = new java.awt.image.BufferedImage(width, height, java.awt.image.BufferedImage.TYPE_INT_ARGB);
+ java.awt.Graphics2D graphics = temp.createGraphics();
+ graphics.drawImage(image, 0, 0, null);
+ graphics.dispose();
}
+
+ byte[] bytes = MapPalette.imageToBytes(temp);
+
+ // Since we now control the size of the image, we can safely use System.arraycopy
+ // If x is 0, we can just copy the entire image as width is 128 and height is <=(128-y)
+ if (x == 0) {
+ System.arraycopy(bytes, 0, this.buffer, y * 128, width * height);
+ return;
+ }
+
+ for (int y2 = 0; y2 < height; ++y2) {
+ System.arraycopy(bytes, 0, this.buffer, (y + y2) * 128 + x, width);
+ }
+ // Paper end
}
@Override
diff --git a/src/main/java/org/bukkit/craftbukkit/map/CraftMapRenderer.java b/src/main/java/org/bukkit/craftbukkit/map/CraftMapRenderer.java
index 0cbbd915631904fe8c6effefb92895422b33eff6..cf0920e5f84b35647882fb963e9972af4e8427e0 100644
--- a/src/main/java/org/bukkit/craftbukkit/map/CraftMapRenderer.java
+++ b/src/main/java/org/bukkit/craftbukkit/map/CraftMapRenderer.java
@@ -23,8 +23,10 @@ public class CraftMapRenderer extends MapRenderer {
@Override
public void render(MapView map, MapCanvas canvas, Player player) {
// Map
- for (int x = 0; x < 128; ++x) {
- for (int y = 0; y < 128; ++y) {
+ // Paper start - Swap inner and outer loops here to (theoretically) improve cache locality
+ for (int y = 0; y < 128; ++y) {
+ for (int x = 0; x < 128; ++x) {
+ // Paper end
canvas.setPixel(x, y, this.worldMap.colors[y * 128 + x]);
}
}