I’ve been puzzling over this one for a while now.
I’m creating a drawing application, where the lines are represented by a Mesh with a MeshCollider. The eraser essentially casts rays in a circular area around the mouse when it is used, however the Raycast never returns true, even though the rays appear to intersect the mesh as shown here:
Here is the relevant code:
void drawEraserCircle(Vector3 mousePos)
{
//Heavy perf hit
//Ideas for optimization: 1) On first mouse click cast rays across entire circle, afterwards only cast rays on the perimeter (where new meshes would be encountered)
// 2) Cast rays every couple pixels instead of every pixel
float radius = 10;
int counter = 0;
for (float y = mousePos.y - radius; y < mousePos.y + radius - 2; y += 2) {
for (float x = mousePos.x - radius; x < mousePos.x + radius - 3; x += 3) {
counter++;
float deltaX = mousePos.x - x;
float deltaY = mousePos.y - y;
double distance = Math.Sqrt((deltaX * deltaX) + (deltaY * deltaY));
// Debug.Log("D " + distance);
//Debug.Log(counter + " X " + x + " Y " + y + " D " + distance + " M " + mousePos);
//Point lies outside of circle
if (distance - radius > 1) {
continue;
}
//Edge threshold
if ((radius / distance) < 0.9) {
continue;
}
//Cast ray to point on circle
Vector3 rayPos = new Vector3(x, y, -100);
Debug.Log(rayPos);
castMeshRay(rayPos);
}
}
}
void castMeshRay(Vector3 rayPos)
{
RaycastHit hit;
Ray ray = new Ray(rayPos, Vector3.forward);
Debug.DrawRay(ray.origin, ray.direction*100, Color.red, 20f, false);
//If ray hits a mesh triangle, delete it
if (Physics.Raycast(ray.origin, ray.direction, out hit, Mathf.Infinity, 1<<6)) //ray never hits???
{
Debug.Log("hit");
selectedMesh = hit.transform.gameObject;
deleteTri(hit.triangleIndex);
}
}
Any suggestions are greatly appreciated, thanks!