fixed an alignment issue in ktx loader

Author: kopaka

DxImageLoader/ktx_interface.cpp

@@ -174,10 +174,27 @@ std::unique_ptr<image::IImage> ktx_load_base(ktxTexture* ktex, gli::format forma
 				ktxLvlSize *= res->getDepth(mip); // is not multiplied with depth layer
 				size_t size;
 				auto dstData = res->getData(dstLayer, mip, size);
-				if (ktxLvlSize != size)
-					throw std::runtime_error("suggested level size of gli does not match with ktx api");
-				memcpy(dstData, ktex->pData + offset, size);
-
+				if(ktxLvlSize == size)
+				{
+					memcpy(dstData, ktex->pData + offset, size); // alignment matches
+				}
+				else if(size < ktxLvlSize)
+				{
+					// calculate size with alignment after each row
+					size_t rows = res->getHeight(mip) * res->getDepth(mip);
+					size_t unalignedRow = size / rows;
+					size_t alignedRow = ktxLvlSize / rows;
+					auto srcData = ktex->pData;
+					//std::vector<uint8_t> debugSrc(srcData, srcData + ktxLvlSize);
+					// copy row by row
+					for(size_t r = 0; r < rows; ++r)
+					{
+						memcpy(dstData, srcData, unalignedRow);
+						dstData += unalignedRow;
+						srcData += alignedRow;
+					}
+				}
+				else throw std::runtime_error("suggested level size of gli does not match with ktx api");
 			}
 			++dstLayer;
 		}

FrameworkTests/ImageLoader/KtxSamples.cs

@@ -1,10 +1,13 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Runtime.InteropServices;
 using System.Text;
 using System.Threading.Tasks;
+using ImageFramework.DirectX;
 using ImageFramework.ImageLoader;
 using ImageFramework.Model;
+using ImageFramework.Utility;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 using SharpDX.DXGI;
 
@@ -17,13 +20,31 @@ public class KtxSamples
 
         public static string ImportBadDir = TestData.Directory + "ktx-software\\badktx2\\";
 
+        public static string ExportDir = TestData.Directory + "export/";
+
+        [ClassInitialize]
+        public static void Init(TestContext context)
+        {
+            TestData.CreateOutputDirectory(ExportDir);
+        }
+
+        private static string[] RemoveUnsupportedFile(string[] files)
+        {
+            // remove all files that have 'eac' or 'etc' in their name (these compressions are not supported yet)
+            return files.Where(f => 
+                !f.Contains("eac") && !f.Contains("EAC") &&
+                !f.Contains("etc") && !f.Contains("ETC")
+            ).ToArray();
+        }
+
         [TestMethod]
         public void ImportTestImagesKtx()
         {
             // get all files in the directory
             var files = System.IO.Directory.GetFiles(ImportDir, "*.ktx", System.IO.SearchOption.TopDirectoryOnly);
             // filter files so they only end with .ktx (not ktx2)
             files = files.Where(f => f.EndsWith(".ktx")).ToArray();
+            files = RemoveUnsupportedFile(files);
             TryImportAllFiles(files);
         }
 
@@ -32,9 +53,41 @@ public void ImportTestImagesKtx2()
         {
             // get all files in the directory
             var files = System.IO.Directory.GetFiles(ImportDir, "*.ktx2", System.IO.SearchOption.TopDirectoryOnly);
+            files = RemoveUnsupportedFile(files);
             TryImportAllFiles(files);
         }
 
+        [TestMethod]
+        public void AlignmentKtx()
+        {
+            // this file uses the RGB format and the width of each row is not a multiple of 4 (this can be tricky to import/export)
+            var filename = ImportDir + "hi_mark_sq.ktx";
+            var model = new Models();
+            model.AddImageFromFile(filename);
+
+            // the following needs to be fulfilled:
+            Assert.AreEqual(145, model.Images.GetWidth(0));
+            Assert.AreEqual(model.Images.Images[0].OriginalFormat, GliFormat.RGB8_UNORM);
+
+            // export and reimport
+            var filename2 = ExportDir + "hi_mark_sq";
+            model.ExportPipelineImage(filename2, "ktx", GliFormat.RGB8_UNORM);
+            
+            // reimport
+            model.AddImageFromFile(filename2 + ".ktx");
+            
+            // compare colors
+            var srcImg = model.Images.Images[0].Image as TextureArray2D;
+            var expImg = model.Images.Images[1].Image as TextureArray2D;
+            Assert.IsNotNull(srcImg);
+            Assert.IsNotNull(expImg);
+
+            var srcColors = srcImg.GetPixelColors(LayerMipmapSlice.Mip0);
+            var expColors = expImg.GetPixelColors(LayerMipmapSlice.Mip0);
+
+            TestData.CompareColors(srcColors, expColors);
+        }
+
         void TryImportAllFiles(string[] files)
         {
             string errors = "";