CreatePreviewEventArgs model lacking UVs in SR12

jdhill · October 15, 2024, 5:17pm

working here with 8.12.24282.7001 on windows, and for an unknown reason, I am getting no UVs on any geometry when I use a ChangeQueue with the CreatePreviewEventArgs passed to CreatePreview, as I have been doing for a long time

the ChangeQueue implementation is the same one used elsewhere in my renderer, it loops over mapping channels or falls back to Mesh.TextureCoordinates and I am getting nothing from either

I have not seen this before, and am not seeing it in 7.37.24107.15001, so it seems like a recent change in v8, and I am wondering if anyone can shed some light on it

dale · November 4, 2024, 11:49pm

@nathanletwory - is this anything you can help with?

nathanletwory · November 5, 2024, 9:12am

As far as I can tell mapping channels have been coming through also in SR12, SRC13 and still internal 8.14.

I set RhinoCycles.VerboseLogging to true, add a pbr material, change its color and check RhinoCyclesShowLog.

I get

11/5/2024 7:27:20AM :: 00:00:00.0073852 |> 	ChangeDatabase ApplyMeshChanges, deleted 0
11/5/2024 7:27:20AM :: 00:00:00.0000005 |> 		ChangeDatabase ApplyMeshChanges added 7
11/5/2024 7:27:20AM :: 00:00:00.0094469 |> 	HandleMeshData: 2308 .. 2500
11/5/2024 7:27:20AM :: 00:00:00.0102605 |> 		HandleMeshData: mapping 0 TextureMapping: (unnamed) (-1) R0=(1,0,0,0), R1=(0,1,0,0), R2=(0,0,1,0), R3=(0,0,0,1)
11/5/2024 7:27:20AM :: 00:00:00.0067162 |> 	HandleMeshData: 1 .. 2
11/5/2024 7:27:20AM :: 00:00:00.0000171 |> 		HandleMeshData: mapping 0 TextureMapping: (unnamed) (-1) R0=(1,0,0,0), R1=(0,1,0,0), R2=(0,0,1,0), R3=(0,0,0,1)
11/5/2024 7:27:20AM :: 00:00:00.0000243 |> 	HandleMeshData: 811 .. 1000
11/5/2024 7:27:20AM :: 00:00:00.0000159 |> 		HandleMeshData: mapping 0 TextureMapping: (unnamed) (-1) R0=(1,0,0,0), R1=(0,1,0,0), R2=(0,0,1,0), R3=(0,0,0,1)
11/5/2024 7:27:20AM :: 00:00:00.0004679 |> 	HandleMeshData: 417 .. 500
11/5/2024 7:27:20AM :: 00:00:00.0000120 |> 		HandleMeshData: mapping 0 TextureMapping: (unnamed) (-1) R0=(1,0,0,0), R1=(0,1,0,0), R2=(0,0,1,0), R3=(0,0,0,1)
11/5/2024 7:27:20AM :: 00:00:00.0001258 |> 	HandleMeshData: 2803 .. 4000
11/5/2024 7:27:20AM :: 00:00:00.0000346 |> 		HandleMeshData: mapping 0 TextureMapping: (unnamed) (-1) R0=(1,0,0,0), R1=(0,1,0,0), R2=(0,0,1,0), R3=(0,0,0,1)
11/5/2024 7:27:20AM :: 00:00:00.0002170 |> 	HandleMeshData: 2214 .. 3516
11/5/2024 7:27:20AM :: 00:00:00.0000310 |> 		HandleMeshData: mapping 0 TextureMapping: (unnamed) (-1) R0=(1,0,0,0), R1=(0,1,0,0), R2=(0,0,1,0), R3=(0,0,0,1)
11/5/2024 7:27:20AM :: 00:00:00.0061164 |> 	HandleMeshData: 758 .. 1000
11/5/2024 7:27:20AM :: 00:00:00.0000173 |> 		HandleMeshData: mapping 0 TextureMapping: (unnamed) (-1) R0=(1,0,0,0), R1=(0,1,0,0), R2=(0,0,1,0), R3=(0,0,0,1)

Adding a breakpoint I see I get UVs after creating those based on the mapping (surface mapping).

@jdhill is this still a problem for you?

jdhill · November 5, 2024, 1:19pm

yes, I am on 8.13.24289.13001 here, I get mapping channels for the objects, but mesh.GetCachedTextureCoordinates(id) returns null, and when I try to fall back to mesh.TextureCoordinates the count is 0

in my code, however, I do not ever create any UVs, I just retrieve what is there, and your mention of “creating those” seems to imply you do something like this

is that what you mean?

(and would this be something considered safe/recommended to be doing all the time, in a changequeue?)

nathanletwory · November 5, 2024, 2:21pm

I don’t use SetCachedTextureCoordinates, but rather SetTextureCoordinates in RhinoCycles:

github.com

mcneel/RhinoCycles/blob/cff59d9b23e6a912afde5ba4cbcf6eb03988aa27/Database/ChangeDatabase.cs#L1082


      
          			if (_renderEngine.ShouldBreak) return;
          			// now convert UVs: from vertex indexed array to per face per vertex
          			if (mappingCollection == null)
          			{
          				// Get texture coordinates and
          				// flattens to a float array.
          				HandleMeshTextureCoordinates(meshdata, findices, cmuvList, 1);
          			} else {
          				foreach(var mapping in mappingCollection.Channels) {
          					RcCore.It.AddLogStringIfVerbose($"\t\tHandleMeshData: mapping {mapping.Mapping.MappingType} {mapping.Channel} {mapping.Mapping} {mapping.Local}");
          					meshdata.SetTextureCoordinates(mapping.Mapping, mapping.Local, false);
          					HandleMeshTextureCoordinates(meshdata, findices, cmuvList, mapping.Channel == 0 ? 1 : mapping.Channel);
          				}
          			}
          
          			var meshid = new Tuple<Guid, int>(meshguid, meshIndex);
          
          			var crc = linearlightMatId==uint.MaxValue ? _objectShaderDatabase.FindRenderHashForMeshId(meshid) : linearlightMatId;
          			if (crc == uint.MaxValue) crc = 0;
          			if (_renderEngine.ShouldBreak) return;

After that I access the TextureCoordinates like this:

github.com

mcneel/RhinoCycles/blob/cff59d9b23e6a912afde5ba4cbcf6eb03988aa27/Database/ChangeDatabase.cs#L1020


      
          
          				idx++;
          			}
          			string sbstr = sb.ToString();
          			RhinoApp.OutputDebugString($"{sbstr}\n\n");
          			return decalList;
          		}
          
          		public void HandleMeshTextureCoordinates(Rhino.Geometry.Mesh meshdata, int[] findices, List<Tuple<int, float[]>> cmuvList, int channelIndex)
          		{
          				var tc = meshdata.TextureCoordinates;
          				var rhuv = tc.ToFloatArray();
          				var cmuv = rhuv.Length > 0 ? new float[findices.Length * 2] : null;
          				if (cmuv != null)
          				{
          					for (var fi = 0; fi < findices.Length; fi++)
          					{
          						if (_renderEngine.ShouldBreak) return;
          						var fioffs = fi * 2;
          						var findex = findices[fi];
          						var findex2 = findex * 2;

What you are seeing could very well be result of work @Jussi_Aaltonen is doing, but he’s currently unavailable to further look into it.

The way I use in RhinoCycles is safe in the ChangeQueue, and I suppose also recommended (:

jdhill · November 5, 2024, 2:53pm

thanks, so in essence you use the mesh.TextureCoordinates as a scratch area, going one by one through the mappings

I have basically treated those as deprecated since forever, only using them if nothing else is available, and though in a changequeue I guess what we do doesn’t affect anything outside, I’d like to hear @andy’s opinion on using those vs. using SetCachedTextureCoordinates, since it is likely I’ll want to use the same code outside of a changequeue at some point, and will not want to disturb whatever someone has put in m_T for whatever reason (e.g. I see from time to time, people posting about issues with finding other coords than “expected” in an exporter or such), and SetCachedTextureCoordinates seems possibly a better choice for that reason

Jussi_Aaltonen · December 27, 2024, 5:27pm

Hi @jdhill
I recommend using SetCachedTextureCoordinates and GetCachedTextureCoordinates. Your code snippet looks correct.

One thing to keep in mind: you should read the UVs from the returned coords object before you call SetCachedTextureCoordinates again on the mesh.

Topic		Replies	Views
Procedural textures + UVW Mapping in Raytracing display mode broken? Rendering windows , texturemapping , displaymodes	7	63	December 11, 2024
UV get lost for rendering (Rhino 6 and 7) Rendering	3	441	October 15, 2020
Accessing mapping channels via RhinoCommon Rhino Developer	6	1234	April 27, 2017
Texture mapping different in viewport and render view Rhino for Windows	6	3910	August 2, 2016
News: Jussi Aaltonen fixed a very important UV mapping bug. And UV mapping start working on Rhino Rhino for Windows windows , uv-mapping	2	846	August 10, 2021

CreatePreviewEventArgs model lacking UVs in SR12

Related topics