public void WriteTwoModelsWithSharedTexture()
{
TestContext.CurrentContext.AttachShowDirLink();
TestContext.CurrentContext.AttachGltfValidatorLinks();
var tex1Bytes = System.IO.File.ReadAllBytes(System.IO.Path.Combine(AssetsPath, "shannon.png"));
var tex2Bytes = System.IO.File.ReadAllBytes(System.IO.Path.Combine(AssetsPath, "Texture1.jpg"));
var tex1 = tex1Bytes.AttachToCurrentTest("shared-shannon.png");
var tex2 = tex2Bytes.AttachToCurrentTest("subdir\\shared-in-dir-Texture1.jpg");
// create a material using our shared texture
var material1 = new MaterialBuilder()
.WithUnlitShader()
.WithBaseColor(tex1);
// create a material using our shared texture
var material2 = new MaterialBuilder()
.WithUnlitShader()
.WithBaseColor(tex2);
// create a simple cube mesh
var mesh1 = new Cube <MaterialBuilder>(material1).ToMesh(Matrix4x4.Identity);
var mesh2 = new Cube <MaterialBuilder>(material2).ToMesh(Matrix4x4.Identity);
var scene = new SceneBuilder();
scene.AddRigidMesh(mesh1, Matrix4x4.CreateTranslation(-2, 0, 0));
scene.AddRigidMesh(mesh2, Matrix4x4.CreateTranslation(2, 0, 0));
var gltf = scene.ToGltf2();
// define the texture sharing hook; this is a pretty naive approach, but it's good
// enough to demonstrate how it works.
string imageSharingHook(WriteContext ctx, string uri, Memory.MemoryImage image)
{
Assert.IsTrue(new string[] { tex1, tex2 }.Contains(image.SourcePath));
if (File.Exists(image.SourcePath))
{
// image.SourcePath is an absolute path, we must make it relative to ctx.CurrentDirectory
var currDir = ctx.CurrentDirectory.FullName + "\\";
// if the shared texture can be reached by the model in its directory, reuse the texture.
if (image.SourcePath.StartsWith(currDir, StringComparison.OrdinalIgnoreCase))
{
// we've found the shared texture!, return the uri relative to the model:
return(image.SourcePath.Substring(currDir.Length));
}
// TODO: Here we could also try to find a texture equivalent to MemoryImage in the
// CurrentDirectory even if it has a different name, to minimize texture duplication.
}
// we were unable to reuse the shared texture,
// default to write our own texture.
image.SaveToFile(Path.Combine(ctx.CurrentDirectory.FullName, uri));
return(uri);
}
var settings = new WriteSettings();
settings.ImageWriting = ResourceWriteMode.SatelliteFile;
settings.ImageWriteCallback = imageSharingHook;
// save the model several times:
var path1 = gltf.AttachToCurrentTest("model1.glb", settings);
var path2 = gltf.AttachToCurrentTest("model2.glb", settings);
var path3 = gltf.AttachToCurrentTest("model3.gltf", settings);
var satellites1 = ModelRoot.GetSatellitePaths(path1);
var satellites2 = ModelRoot.GetSatellitePaths(path2);
var satellites3 = ModelRoot.GetSatellitePaths(path3);
Assert.IsTrue(satellites1.Contains("shared-shannon.png"));
Assert.IsTrue(satellites1.Contains("subdir/shared-in-dir-Texture1.jpg"));
Assert.IsTrue(satellites2.Contains("shared-shannon.png"));
Assert.IsTrue(satellites2.Contains("subdir/shared-in-dir-Texture1.jpg"));
Assert.IsTrue(satellites3.Contains("shared-shannon.png"));
Assert.IsTrue(satellites3.Contains("subdir/shared-in-dir-Texture1.jpg"));
}
public static bool AreEqualByContent(MaterialBuilder x, MaterialBuilder y)
{
#pragma warning disable IDE0041 // Use 'is null' check
if (Object.ReferenceEquals(x, y))
{
return(true);
}
if (Object.ReferenceEquals(x, null))
{
return(false);
}
if (Object.ReferenceEquals(y, null))
{
return(false);
}
#pragma warning restore IDE0041 // Use 'is null' check
// Although .Name is not strictly a material property,
// it identifies a specific material during Runtime that
// might be relevant and needs to be preserved.
// If an author needs materials to be merged, it's better
// to keep the Name as null, or to use a common name like "Default".
if (x.Name != y.Name)
{
return(false);
}
if (x.AlphaMode != y.AlphaMode)
{
return(false);
}
if (x.AlphaCutoff != y.AlphaCutoff)
{
return(false);
}
if (x.DoubleSided != y.DoubleSided)
{
return(false);
}
if (x.ShaderStyle != y.ShaderStyle)
{
return(false);
}
if (!AreEqualByContent(x._CompatibilityFallbackMaterial, y._CompatibilityFallbackMaterial))
{
return(false);
}
// gather all unique channel keys used by both materials.
var channelKeys = x._Channels
.Concat(y._Channels)
.Select(item => item.Key)
.Distinct();
foreach (var ckey in channelKeys)
{
var xc = x.GetChannel(ckey);
var yc = y.GetChannel(ckey);
if (!ChannelBuilder.AreEqual(xc, yc))
{
return(false);
}
}
return(true);
}