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--- 1.0.0:pathfinding [2023/03/21 15:29] – [Click to Start Pathfinding] admin
+++ 1.0.0:pathfinding [2023/03/21 15:33] – [Click to Start Pathfinding] admin
@@ Line 155: / Line 155: @@
 Image1.Bitmap.Assign(FVerifyBmp);
 </file>
+===== Click to Start Pathfinding  =====
+Many developers may struggle with the question how to combine the setup above with user interaction.
+Speaking for a classic Point & Click Adventure, a recommend way is to add a simple plane (TPlane, TGorillaPlane) for click detection.
+All other 3D elements should be set to HitTest = false, to not disturb mouse interaction with the helper plane.
+We then register a MouseUp event on the viewport, where we put all of our mouse handling.
+<file pascal>
+var
+  FDestPoint : TPoint3D;
+procedure TForm1.GorillaViewport1MouseUp(Sender: TObject; Button: TMouseButton;
+  Shift: TShiftState; X, Y: Single);
+var LRayPos,
+    LRayDir : TPoint3D;
+    LHitPos,
+    LNormal,
+    LScreenPos : TPoint3D;
+begin
+  // 1) Get 3D position of click, by converting screen coordinates into 3D coordinates
+  LScreenPos := GorillaViewport1.ScreenToWorld(PointF(X, Y));
+  // 2) Cast a ray from camera to the clicking position, to retrieve the real
+  //    3D destination coordinate
+  LRayPos := GorillaCamera1.AbsolutePosition;
+  LRayDir := (LScreenPos - LRayPos).Normalize();
+  if GorillaPlane1.RayCastIntersect(LRayPos, LRayDir, LHitPos, LNormal) then
+  begin
+    // If raycasting was successfully - we can start store the point hit by the ray
+    FDestPoint := LHitPos;
+    FDestPoint.Y := 0;
+    // Aftwards we start pathfinding
+    UpdatePathfinding();
+  end;
+end;
+procedure TForm1.UpdatePathfinding();
+var LAgentPos : TPoint3D;
+begin
+  // Get the agent position (pathfinding moving object)
+  LAgentPos := GorillaModel1.AbsolutePosition;
+  // Compute the path from 3D position - this will generate our new walking path
+  FPathFinder.FindPath(LAgentPos, FDestPoint);
+  // Stop the current animation
+  FPathAnim.Stop();
+  FPathAnim.Enabled := false;
+  // Apply computed path data to our existing TGorillaPath3D instance, instead for recreating each time
+  FPathFinder.ApplyToPath3D(FPath);
+  // Reset the used path data in our path animation
+  FPathAnim.Duration := FPath.Path.GetLength;
+  FPathAnim.Path := FPath.Path;
+  // For correct rotation of our character, we need the polygon to detect the
+  // next node to adjust to
+  FPath.Path.FlattenToPolygon(FPolygon);
+  // Restart movement on path
+  FPathAnim.Enabled := true;
+  FPathAnim.Start();
+end;
+</file>
 ===== Auto-Rotate an animated character =====
@@ Line 228: / Line 300: @@
 </file>
-===== Click to Start Pathfinding  =====
-Many developers may struggle with the question how to combine the setup above with user interaction.
-Speaking for a classic Point & Click Adventure, a recommend way is to add a simple plane (TPlane, TGorillaPlane) for click detection.
-All other 3D elements should be set to HitTest = false, to not disturb mouse interaction with the helper plane.
-We then register a MouseUp event on the viewport, where we put all of our mouse handling.
-<file pascal>
-var
-  FDestPoint : TPoint3D;
-procedure TForm1.GorillaViewport1MouseUp(Sender: TObject; Button: TMouseButton;
-  Shift: TShiftState; X, Y: Single);
-var LRayPos,
-    LRayDir : TPoint3D;
-    LHitPos,
-    LNormal,
-    LScreenPos : TPoint3D;
-begin
-  // 1) Get 3D position of click, by converting screen coordinates into 3D coordinates
-  LScreenPos := GorillaViewport1.ScreenToWorld(PointF(X, Y));
-  // 2) Cast a ray from camera to the clicking position, to retrieve the real
-  //    3D destination coordinate
-  LRayPos := GorillaCamera1.AbsolutePosition;
-  LRayDir := (LScreenPos - LRayPos).Normalize();
-  if GorillaPlane1.RayCastIntersect(LRayPos, LRayDir, LHitPos, LNormal) then
-  begin
-    // If raycasting was successfull - we can start updating the path
-    FDestPoint := LHitPos;
-    FDestPoint.Y := 0;
-    // Start pathfinding
-    UpdatePathfinding();
-  end;
-end;
-procedure TForm1.UpdatePathfinding();
-var LAgentPos : TPoint3D;
-begin
-  // New computation of path
-  LAgentPos := GorillaModel1.AbsolutePosition;
-  FPathFinder.FindPath(LAgentPos, FDestPoint);
-  // Stop the current animation
-  FPathAnim.Stop();
-  FPathAnim.Enabled := false;
-  // Apply computed path data to our existing TGorillaPath3D instance, instead for recreating each time
-  FPathFinder.ApplyToPath3D(FPath);
-  // Reset the used path data in our path animation
-  FPathAnim.Duration := FPath.Path.GetLength;
-  FPathAnim.Path := FPath.Path;
-  // For correct rotation of our character, we need the polygon to detect the
-  // next node to adjust to
-  FPath.Path.FlattenToPolygon(FPolygon);
-  // Restart movement on path
-  FPathAnim.Enabled := true;
-  FPathAnim.Start();
-end;
-</file>
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