public void ScatterAlphamap(string editorUndoName)
{
Vector4[] layerMasks = { new Vector4(1, 0, 0, 0), new Vector4(0, 1, 0, 0), new Vector4(0, 0, 1, 0), new Vector4(0, 0, 0, 1) };
Material copyTerrainLayerMaterial = TerrainPaintUtility.GetCopyTerrainLayerMaterial();
var rtdesc = new RenderTextureDescriptor(destinationRenderTexture.width, destinationRenderTexture.height, RenderTextureFormat.ARGB32);
rtdesc.sRGB = false;
rtdesc.useMipMap = false;
rtdesc.autoGenerateMips = false;
RenderTexture tempTarget = RenderTexture.GetTemporary(rtdesc);
ScatterInternal(
t => // We're going to do ALL of the work in this terrainToRT function, as it is very custom, and we'll just return null to skip the ScatterInternal rendering
{
SplatmapUserData userData = GetTerrainLayerUserData(t);
if (userData != null)
{
onTerrainTileBeforePaint?.Invoke(t, ToolAction.PaintTexture, editorUndoName);
int targetAlphamapIndex = userData.mapIndex;
int targetChannelIndex = userData.channelIndex;
Texture2D targetAlphamapTexture = t.terrain.terrainData.alphamapTextures[targetAlphamapIndex];
destinationRenderTexture.filterMode = FilterMode.Point;
sourceRenderTexture.filterMode = FilterMode.Point;
// iterate all alphamaps to modify them (have to modify all to renormalize)
for (int i = 0; i <= t.terrain.terrainData.alphamapTextureCount; i++) // NOTE: this is a non-standard for loop
{
// modify the target index last, (skip it the first time)
if (i == targetAlphamapIndex)
{
continue;
}
int alphamapIndex = (i == t.terrain.terrainData.alphamapTextureCount) ? targetAlphamapIndex : i;
Texture2D alphamapTexture = t.terrain.terrainData.alphamapTextures[alphamapIndex];
if ((alphamapTexture.width != targetTextureWidth) || (alphamapTexture.height != targetTextureHeight))
{
Debug.LogWarning("PaintContext alphamap operations must use the same resolution for all Terrains - mismatched Terrains are ignored.", t.terrain);
continue;
}
RenderTexture.active = tempTarget;
GL.PushMatrix();
GL.LoadPixelMatrix(0, tempTarget.width, 0, tempTarget.height);
{
copyTerrainLayerMaterial.SetTexture("_MainTex", destinationRenderTexture);
copyTerrainLayerMaterial.SetTexture("_OldAlphaMapTexture", sourceRenderTexture);
copyTerrainLayerMaterial.SetTexture("_OriginalTargetAlphaMap", targetAlphamapTexture);
copyTerrainLayerMaterial.SetTexture("_AlphaMapTexture", alphamapTexture);
copyTerrainLayerMaterial.SetVector("_LayerMask", alphamapIndex == targetAlphamapIndex ? layerMasks[targetChannelIndex] : Vector4.zero);
copyTerrainLayerMaterial.SetVector("_OriginalTargetAlphaMask", layerMasks[targetChannelIndex]);
copyTerrainLayerMaterial.SetPass(1);
TerrainPaintUtility.DrawQuad2(t.clippedPCPixels, t.clippedPCPixels, destinationRenderTexture, t.clippedTerrainPixels, alphamapTexture);
}
GL.PopMatrix();
t.terrain.terrainData.CopyActiveRenderTextureToTexture(TerrainData.AlphamapTextureName, alphamapIndex, t.clippedPCPixels, t.clippedTerrainPixels.min, true);
}
RenderTexture.active = null;
OnTerrainPainted(t, ToolAction.PaintTexture);
}
return(null);
},
"PaintContext.ScatterAlphamap",
copyTerrainLayerMaterial, 0);
RenderTexture.ReleaseTemporary(tempTarget);
}
internal static void DrawQuad(RectInt destinationPixels, RectInt sourcePixels, Texture sourceTexture)
{
TerrainPaintUtility.DrawQuad2(destinationPixels, sourcePixels, sourceTexture, sourcePixels, sourceTexture);
}