void DrawEdge(MeshGenerationContext mgc)
{
if (edgeWidth <= 0)
{
return;
}
UpdateRenderPoints();
if (m_RenderPoints.Count == 0)
{
return; // Don't draw anything
}
Color inColor = this.inputColor;
Color outColor = this.outputColor;
#if UNITY_EDITOR
inColor *= GraphViewStaticBridge.EditorPlayModeTint;
outColor *= GraphViewStaticBridge.EditorPlayModeTint;
#endif // UNITY_EDITOR
uint cpt = (uint)m_RenderPoints.Count;
uint wantedLength = (cpt) * 2;
uint indexCount = (wantedLength - 2) * 3;
var md = GraphViewStaticBridge.AllocateMeshWriteData(mgc, (int)wantedLength, (int)indexCount);
if (md.vertexCount == 0)
{
return;
}
float polyLineLength = 0;
for (int i = 1; i < cpt; ++i)
{
polyLineLength += (m_RenderPoints[i - 1] - m_RenderPoints[i]).sqrMagnitude;
}
float halfWidth = edgeWidth * 0.5f;
float currentLength = 0;
Vector2 unitPreviousSegment = Vector2.zero;
for (int i = 0; i < cpt; ++i)
{
Vector2 dir;
Vector2 unitNextSegment = Vector2.zero;
Vector2 nextSegment = Vector2.zero;
if (i < cpt - 1)
{
nextSegment = (m_RenderPoints[i + 1] - m_RenderPoints[i]);
unitNextSegment = nextSegment.normalized;
}
if (i > 0 && i < cpt - 1)
{
dir = unitPreviousSegment + unitNextSegment;
dir.Normalize();
}
else if (i > 0)
{
dir = unitPreviousSegment;
}
else
{
dir = unitNextSegment;
}
Vector2 pos = m_RenderPoints[i];
Vector2 uv = new Vector2(dir.y * halfWidth, -dir.x * halfWidth); // Normal scaled by half width
Color32 tint = Color.LerpUnclamped(outColor, inColor, currentLength / polyLineLength);
md.SetNextVertex(new Vector3(pos.x, pos.y, 1), uv, tint);
md.SetNextVertex(new Vector3(pos.x, pos.y, -1), uv, tint);
if (i < cpt - 2)
{
currentLength += nextSegment.sqrMagnitude;
}
else
{
currentLength = polyLineLength;
}
unitPreviousSegment = unitNextSegment;
}
// Fill triangle indices as it is a triangle strip
for (uint i = 0; i < wantedLength - 2; ++i)
{
if ((i & 0x01) == 0)
{
md.SetNextIndex((UInt16)i);
md.SetNextIndex((UInt16)(i + 2));
md.SetNextIndex((UInt16)(i + 1));
}
else
{
md.SetNextIndex((UInt16)i);
md.SetNextIndex((UInt16)(i + 1));
md.SetNextIndex((UInt16)(i + 2));
}
}
}
