// this function sets up material properties used by functions provided in TerrainTool.cginc
public static void SetupTerrainToolMaterialProperties(
PaintContext paintContext,
BrushTransform brushXform, // the brush transform to terrain space (of paintContext.originTerrain)
Material material)
{
// BrushUV = f(terrainSpace.xz) = f(g(pc.uv))
// f(ts.xy) = ts.x * brushXform.X + ts.y * brushXform.Y + brushXform.Origin
// g(pc.uv) = ts.xz = pcOrigin + pc.uv * pcSize
// f(g(pc.uv)) == (pcOrigin + pc.uv * pcSize).x * brushXform.X + (pcOrigin + pc.uv * pcSize).y * brushXform.Y + brushXform.Origin
// f(g(pc.uv)) == (pcOrigin.x + pc.u * pcSize.x) * brushXform.X + (pcOrigin.y + pc.v * pcSize.y) * brushXform.Y + brushXform.Origin
// f(g(pc.uv)) == (pcOrigin.x * brushXform.X) + (pc.u * pcSize.x) * brushXform.X + (pcOrigin.y * brushXform.Y) + (pc.v * pcSize.y) * brushXform.Y + brushXform.Origin
// f(g(pc.uv)) == pc.u * (pcSize.x * brushXform.X) + pc.v * (pcSize.y * brushXform.Y) + (brushXform.Origin + (pcOrigin.x * brushXform.X) + (pcOrigin.y * brushXform.Y))
// pcOrigin = (pc.pixelRect.xyMin - 0.5) * pc.pixelSize.xy
// pcSize = (pc.pixelRect.wh) * pc.pixelSize.xy
// paint context origin in terrain space
// (note this is the UV space origin and size, not the mesh origin & size)
float pcOriginX = (paintContext.pixelRect.xMin - 0.5f) * paintContext.pixelSize.x;
float pcOriginZ = (paintContext.pixelRect.yMin - 0.5f) * paintContext.pixelSize.y;
float pcSizeX = (paintContext.pixelRect.width) * paintContext.pixelSize.x;
float pcSizeZ = (paintContext.pixelRect.height) * paintContext.pixelSize.y;
Vector2 scaleU = pcSizeX * brushXform.targetX;
Vector2 scaleV = pcSizeZ * brushXform.targetY;
Vector2 offset = brushXform.targetOrigin + pcOriginX * brushXform.targetX + pcOriginZ * brushXform.targetY;
material.SetVector("_PCUVToBrushUVScales", new Vector4(scaleU.x, scaleU.y, scaleV.x, scaleV.y));
material.SetVector("_PCUVToBrushUVOffset", new Vector4(offset.x, offset.y, 0.0f, 0.0f));
}
public static BrushTransform CalculateBrushTransform(Terrain terrain, Vector2 brushCenterTerrainUV, float brushSize, float brushRotationDegrees)
{
float f = brushRotationDegrees * 0.0174532924f;
float num = Mathf.Cos(f);
float num2 = Mathf.Sin(f);
Vector2 vector = new Vector2(num, -num2) * brushSize;
Vector2 vector2 = new Vector2(num2, num) * brushSize;
Vector3 size = terrain.terrainData.size;
Vector2 a = brushCenterTerrainUV * new Vector2(size.x, size.z);
Vector2 brushOrigin = a - 0.5f * vector - 0.5f * vector2;
BrushTransform result = new BrushTransform(brushOrigin, vector, vector2);
return(result);
}
// returns a transform from terrain space to brush UV
public static BrushTransform CalculateBrushTransform(
Terrain terrain, Vector2 brushCenterTerrainUV, float brushSize, float brushRotationDegrees)
{
float rotationRadians = brushRotationDegrees * Mathf.Deg2Rad;
float cos = Mathf.Cos(rotationRadians);
float sin = Mathf.Sin(rotationRadians);
Vector2 brushU = new Vector2(cos, -sin) * brushSize;
Vector2 brushV = new Vector2(sin, cos) * brushSize;
// calculate brush origin
Vector3 terrainSize = terrain.terrainData.size;
Vector2 brushCenterTerrainSpace = brushCenterTerrainUV * new Vector2(terrainSize.x, terrainSize.z);
Vector2 brushOrigin = brushCenterTerrainSpace - 0.5f * brushU - 0.5f * brushV;
BrushTransform xform = new BrushTransform(brushOrigin, brushU, brushV);
return(xform);
}
public static void SetupTerrainToolMaterialProperties(PaintContext paintContext, BrushTransform brushXform, Material material)
{
float d = ((float)paintContext.pixelRect.xMin - 0.5f) * paintContext.pixelSize.x;
float d2 = ((float)paintContext.pixelRect.yMin - 0.5f) * paintContext.pixelSize.y;
float d3 = (float)paintContext.pixelRect.width * paintContext.pixelSize.x;
float d4 = (float)paintContext.pixelRect.height * paintContext.pixelSize.y;
Vector2 vector = d3 * brushXform.targetX;
Vector2 vector2 = d4 * brushXform.targetY;
Vector2 vector3 = brushXform.targetOrigin + d * brushXform.targetX + d2 * brushXform.targetY;
material.SetVector("_PCUVToBrushUVScales", new Vector4(vector.x, vector.y, vector2.x, vector2.y));
material.SetVector("_PCUVToBrushUVOffset", new Vector4(vector3.x, vector3.y, 0f, 0f));
}
