Differences

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--- 1.1.0:picking [2024/04/09 15:46] – admin
+++ 1.1.0:picking [2024/04/09 15:58] – admin
@@ Line 26: / Line 26: @@
     Triangle     : Array[0..2] of TPoint3D;
   end;
+</file>
+As example, you can register an OnMouseUp event on your specific mesh/model or sub-mesh.
+Within your OnMouseUp event you can then perform the raycasting or triangle picking:
+<file Pascal>
+procedure TForm1.MyMeshMouseUp(Sender: TObject; Button: TMouseButton;
+  Shift: TShiftState; X, Y: Single; RayPos, RayDir: TVector3D);
+var LAbsRayPos, LAbsRayDir : TVector3D;
+    LIntersect, LNormal : TPoint3D;
+    LMesh : TGorillaMesh;
+    LTriResult  : TTriangleRayCastResult;
+begin
+  LMesh := Sender as TGorillaMesh;
+  if not Assigned(LMesh) then
+    Exit;
+  // Convert from local vector to absolute, because we're currently in object space
+  LAbsRayPos := LMesh.LocalToAbsoluteVector(ARayPos);
+  LAbsRayDir := LMesh.LocalToAbsoluteDirection(ARayDir);
+  // Perform a raycast intersection test and if it hits the mesh, show a message
+  if LMesh.RayCastIntersect(LAbsRayPos, LAbsRayDir, LIntersect, LNormal) then
+    ShowMessage(Format('Intersection-Point = (%n, %n, %n)', [LIntersect.X, LIntersect.Y, LIntersect.Z]));
+  // Or perform a triangle pick and output the triangle points and the instance pointer too
+  if LMesh.PickTriangle(LAbsRayPos, LAbsRayDir, LTriResult) then
+    ShowMessage(Format('instance=%d, Intersection-Point = (%n, %n, %n), triangle-P1=(%n,%n,%n), triangle-P2=(%n,%n,%n), triangle-P3=(%n,%n,%n)',
+      [
+      NativeUInt(LTriResult.Instance),
+      LTriResult.Intersection.X, LTriResult.Intersection.Y, LTriResult.Intersection.Z,
+      LTriResult.Triangle[0].X, LTriResult.Triangle[0].Y, LTriResult.Triangle[0].Z,
+      LTriResult.Triangle[1].X, LTriResult.Triangle[1].Y, LTriResult.Triangle[1].Z,
+      LTriResult.Triangle[2].X, LTriResult.Triangle[2].Y, LTriResult.Triangle[2].Z
+      ]));
+end;
 </file>