/// Converts TiltBrush brush strokes into linear USD BasisCurves.
static BrushCurvesSample GetCurvesSample(ExportUtils.SceneStatePayload payload,
List <Stroke> strokes,
Matrix4x4 mat44)
{
var sample = new BrushCurvesSample();
var times = new List <float>();
var pressures = new List <float>();
sample.doubleSided = true;
sample.orientation = USD.NET.Orientation.LeftHanded;
sample.basis = BasisCurvesSample.Basis.Bezier;
sample.type = BasisCurvesSample.CurveType.Linear;
sample.wrap = BasisCurvesSample.WrapMode.Nonperiodic;
sample.curveVertexCounts = strokes.Select(x => x.m_ControlPoints.Length).ToArray();
sample.transform = mat44;
int numCPs = sample.curveVertexCounts.Sum();
sample.points = new Vector3[numCPs];
sample.normals = new Vector3[numCPs];
sample.colors = new Color[numCPs];
int iKnot = 0;
foreach (Stroke stroke in strokes)
{
foreach (var cp in stroke.m_ControlPoints)
{
times.Add(cp.m_TimestampMs / 1000.0f);
pressures.Add(cp.m_Pressure);
}
foreach (var cp in stroke.m_ControlPoints)
{
// Normals in USD are stored in object/local space, just as points are.
sample.normals[iKnot] = cp.m_Orient * Vector3.up;
sample.points[iKnot] = cp.m_Pos;
sample.colors[iKnot] = stroke.m_Color.linear;
iKnot++;
}
}
{
Matrix4x4 basis = ExportUtils.GetFromUnity_Axes(payload);
Matrix4x4 units = Matrix4x4.Scale(Vector3.one * payload.exportUnitsFromAppUnits);
MathUtils.TransformVector3AsPoint(units * basis, 0, sample.points.Length, sample.points);
MathUtils.TransformVector3AsVector(basis, 0, sample.normals.Length, sample.normals);
}
sample.extent = new Bounds(sample.points[0], Vector3.zero);
for (int i = 0; i < sample.points.Length; i++)
{
sample.extent.Encapsulate(sample.points[i]);
}
sample.times = times.ToArray();
sample.pressures = pressures.ToArray();
return(sample);
}
public static void Export(string outputFile)
{
float scale = 100f;
ExportUtils.SceneStatePayload payload = ExportCollector.GetExportPayload(AxisConvention.kStl);
var buffer = new StringBuilder();
foreach (var group in payload.groups)
{
foreach (var brushMeshPayload in group.brushMeshes)
{
var pool = brushMeshPayload.geometry;
var xf = brushMeshPayload.xform;
var name = brushMeshPayload.legacyUniqueName;
buffer.AppendFormat("solid {0}\n", name);
for (int i = 0; i < pool.NumTriIndices; i += 3)
{
Vector3 normal = (pool.m_Normals[pool.m_Tris[i]] +
pool.m_Normals[pool.m_Tris[i + 1]] +
pool.m_Normals[pool.m_Tris[i + 2]]) / 3f;
normal.Normalize();
normal = xf.MultiplyVector(normal);
Vector3 v1 = xf * pool.m_Vertices[pool.m_Tris[i]] * scale;
Vector3 v2 = xf * pool.m_Vertices[pool.m_Tris[i + 1]] * scale;
Vector3 v3 = xf * pool.m_Vertices[pool.m_Tris[i + 2]] * scale;
buffer.AppendFormat(" facet normal {0} {1} {2}\n", normal.x, normal.y, normal.z);
buffer.Append(" outer loop\n");
buffer.AppendFormat(" vertex {0} {1} {2}\n", v1.x, v1.y, v1.z);
buffer.AppendFormat(" vertex {0} {1} {2}\n", v2.x, v2.y, v2.z);
buffer.AppendFormat(" vertex {0} {1} {2}\n", v3.x, v3.y, v3.z);
buffer.Append(" endloop\n");
buffer.Append(" endfacet\n");
}
buffer.AppendFormat("endsolid {0}\n", name);
}
}
System.IO.File.WriteAllText(outputFile, buffer.ToString());
}
// Populates glTF metadata and scene extras fields.
private void SetExtras(
GlTF_ScriptableExporter exporter, ExportUtils.SceneStatePayload payload)
{
Color skyColorA = payload.env.skyColorA;
Color skyColorB = payload.env.skyColorB;
Vector3 skyGradientDir = payload.env.skyGradientDir;
// Scene-level extras:
exporter.G.extras["TB_EnvironmentGuid"] = payload.env.guid.ToString("D");
exporter.G.extras["TB_Environment"] = payload.env.description;
exporter.G.extras["TB_UseGradient"] = payload.env.useGradient ? "true" : "false";
exporter.G.extras["TB_SkyColorA"] = CommaFormattedFloatRGB(skyColorA);
exporter.G.extras["TB_SkyColorB"] = CommaFormattedFloatRGB(skyColorB);
Matrix4x4 exportFromUnity = AxisConvention.GetFromUnity(payload.axes);
exporter.G.extras["TB_SkyGradientDirection"] = CommaFormattedVector3(
exportFromUnity * skyGradientDir);
exporter.G.extras["TB_FogColor"] = CommaFormattedFloatRGB(payload.env.fogColor);
exporter.G.extras["TB_FogDensity"] = payload.env.fogDensity.ToString();
// TODO: remove when Poly starts using the new color data
exporter.G.extras["TB_SkyColorHorizon"] = CommaFormattedFloatRGB(skyColorA);
exporter.G.extras["TB_SkyColorZenith"] = CommaFormattedFloatRGB(skyColorB);
}
public static bool Export(string outputFile) {
ExportUtils.SceneStatePayload payload = ExportCollector.GetExportPayload(AxisConvention.kVrml);
var buffer = new StringBuilder("#VRML V2.0 utf8\n");
AppendSceneHeader(ref buffer);
foreach (var group in payload.groups) {
foreach (var brushMeshPayload in group.brushMeshes) {
var pool = brushMeshPayload.geometry;
Color32 lastColor = pool.m_Colors[0]; // Set to color of first vert initially
int j = 0; // An index marking current position in pool.m_Tris
int numVerts = 0; // Number of verts appended
int firstVertInchunk = 0; // So chunks starts triangle-indexing verts at 0 in the wrl
AppendchunkHeader(ref buffer);
AppendchunkVerticesHeader(ref buffer);
// Iterate through the verts-array and append them to the wrl.
// Upon hitting a vertex with a different color (a new chunk), backtrack and iterate
// through the tris-array, appending all triangles that are in the current chunk.
// Continue again with the new chunk, etc., until all vertices are appended.
for (int i = 0; i < pool.NumVerts; i++) {
Color32 curColor = pool.m_Colors[i];
if (curColor.Equals(lastColor)) { // In the same chunk
AppendVertex(ref buffer, pool, i);
numVerts += 1;
if (i == pool.NumVerts - 1) { // last vertex
AppendchunkVerticesFooter(ref buffer);
AppendchunkTrianglesHeader(ref buffer);
while (j < pool.NumTriIndices) { // Append all remaining triangles
AppendTriangle(ref buffer, pool, j, firstVertInchunk);
j += 3;
}
AppendchunkTrianglesFooter(ref buffer);
AppendchunkAppearanceHeader(ref buffer);
AppendColorRGB(ref buffer, lastColor);
AppendColorA(ref buffer, lastColor);
AppendchunkAppearanceFooter(ref buffer);
AppendchunkFooter(ref buffer);
}
} else { // New color, so new chunk
AppendchunkVerticesFooter(ref buffer);
AppendchunkTrianglesHeader(ref buffer);
// Vertex "i" is part of a new chunk, therefore only append
// triangles that contain vertices up to and not including "i"
while (j < pool.NumTriIndices) {
// Only check first index in triangle because triangles cannot span across chunks.
// Either all vertices of the triangle are in chunk_n or all are in chunk_n+1.
if (pool.m_Tris[j] < i) {
AppendTriangle(ref buffer, pool, j, firstVertInchunk);
j += 3;
} else {
break;
}
}
AppendchunkTrianglesFooter(ref buffer);
AppendchunkAppearanceHeader(ref buffer);
AppendColorRGB(ref buffer, lastColor);
AppendColorA(ref buffer, lastColor);
AppendchunkAppearanceFooter(ref buffer);
AppendchunkFooter(ref buffer);
AppendchunkHeader(ref buffer); // Starting the next chunk
AppendchunkVerticesHeader(ref buffer);
AppendVertex(ref buffer, pool, i);
firstVertInchunk = numVerts;
numVerts += 1;
lastColor = curColor;
}
}
}
}
AppendSceneFooter(ref buffer);
System.IO.File.WriteAllText(outputFile, buffer.ToString());
return true;
}
