From 89a41fc962d3f9f3444eea11874d59a15d279d9a Mon Sep 17 00:00:00 2001
From: Paul Wedeck <paulwedeck@gmail.com>
Date: Tue, 24 Jan 2023 19:58:32 +0100
Subject: [PATCH] add necessary format conversion to GLESDrawContext and
 OriginalImageProvider

---
 .../go/graphics/android/GLESDrawContext.java  | 26 +++++++++++++++++--
 .../core/resources/OriginalImageProvider.java | 16 +++++++++++-
 2 files changed, 39 insertions(+), 3 deletions(-)

diff --git a/go.graphics.android/src/main/java/go/graphics/android/GLESDrawContext.java b/go.graphics.android/src/main/java/go/graphics/android/GLESDrawContext.java
index a9e2385f8..f03a81b9c 100644
--- a/go.graphics.android/src/main/java/go/graphics/android/GLESDrawContext.java
+++ b/go.graphics.android/src/main/java/go/graphics/android/GLESDrawContext.java
@@ -24,6 +24,7 @@
 import java.io.InputStreamReader;
 import java.nio.ByteBuffer;
 import java.nio.FloatBuffer;
+import java.nio.IntBuffer;
 import java.util.ArrayList;
 
 import go.graphics.AbstractColor;
@@ -117,9 +118,30 @@ public TextureHandle generateTexture(ImageData image, String name) {
 		return texture;
 	}
 
+	private ImageData fixFormat(ImageData orig) {
+		if(orig == null) return null;
+
+		ImageData conv = new ImageData(orig.getWidth(), orig.getHeight());
+		IntBuffer from = orig.getReadData32();
+		IntBuffer to = conv.getWriteData32();
+		while(from.hasRemaining()) {
+			int pixel = from.get();
+			int r = pixel&0xFF;
+			int g = (pixel>>8)&0xFF;
+			int b = (pixel>>16)&0xFF;
+			int a = (pixel>>24)&0xFF;
+
+			int reversed = r<<24 | g << 16 | b << 8 | a;
+			to.put(reversed);
+		}
+
+		to.rewind();
+		return conv;
+	}
+
 	public TextureHandle resizeTexture(TextureHandle textureIndex, ImageData image) {
 		bindTexture(textureIndex);
-		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, image.getWidth(), image.getHeight(), 0, GL_RGBA, GL_UNSIGNED_BYTE, image.getReadData32());
+		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, image.getWidth(), image.getHeight(), 0, GL_RGBA, GL_UNSIGNED_BYTE, fixFormat(image).getReadData32());
 		return textureIndex;
 	}
 
@@ -127,7 +149,7 @@ public void updateTexture(TextureHandle textureIndex, int left, int bottom,
 							  ImageData image) {
 		bindTexture(textureIndex);
 		glTexSubImage2D(GL_TEXTURE_2D, 0, left, bottom, image.getWidth(), image.getHeight(),
-				GL_RGBA, GL_UNSIGNED_BYTE, image.getReadData32());
+				GL_RGBA, GL_UNSIGNED_BYTE, fixFormat(image).getReadData32());
 	}
 
 	protected void bindTexture(TextureHandle texture) {
diff --git a/jsettlers.main.android/src/main/java/jsettlers/main/android/core/resources/OriginalImageProvider.java b/jsettlers.main.android/src/main/java/jsettlers/main/android/core/resources/OriginalImageProvider.java
index 50e498e7f..2bdc27822 100644
--- a/jsettlers.main.android/src/main/java/jsettlers/main/android/core/resources/OriginalImageProvider.java
+++ b/jsettlers.main.android/src/main/java/jsettlers/main/android/core/resources/OriginalImageProvider.java
@@ -15,6 +15,8 @@
 
 package jsettlers.main.android.core.resources;
 
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
 import java.nio.IntBuffer;
 import java.nio.ShortBuffer;
 import java.util.ArrayList;
@@ -97,6 +99,18 @@ public ImageReference(ImageLink image) {
 			this.image = image;
 		}
 
+
+		private IntBuffer fixRGBA8Buffer(IntBuffer orig) {
+			IntBuffer bfr = ByteBuffer.allocateDirect(orig.remaining()*4).order(ByteOrder.nativeOrder()).asIntBuffer();
+			while(orig.hasRemaining()) {
+				int color = orig.get();
+				bfr.put(((color<<24)&0xFF000000) | ((color >> 8)&0xFFFFFF));
+			}
+			orig.rewind();
+			bfr.rewind();
+			return bfr;
+		}
+
 		public void load() {
 			Image loaded = ImageProvider.getInstance().getImage(image);
 			int[] colors = new int[1];
@@ -105,7 +119,7 @@ public void load() {
 
 			if (loaded instanceof SingleImage) {
 				ImageData data = ((SingleImage) loaded).getData();
-				IntBuffer bfr = data.getReadData32();
+				IntBuffer bfr = fixRGBA8Buffer(data.getReadData32());
 
 				width = data.getWidth();
 				height = data.getHeight();