public void DrawCircle(Vector2 pos, float radius, float z, Color4 color, float borderThickness, Color4 borderColor)
{
var innerRadius = radius - borderThickness;
var outer = Affine.Translation(pos) * Affine.Scale(radius);
var inner = Affine.Translation(pos) * Affine.Scale(innerRadius);
_chunkBuffer.AddConvexChunk(_unitCircleVerts, z, color, inner);
_chunkBuffer.AddBorderChunk(_unitCircleVerts.Select(x => inner * x).ToArray(),
_unitCircleVerts.Select(x => outer * x).ToArray(),
z, borderColor);
}