#5746: Getting the transformation on patches to be correct, undoable …

…and live-updating the views seems to be very complicated. Its freezeTransform() behaviour is quite different from faces, which might be an indication of one or more design issues. Patch::controlPointsChanged() does way too much, including revertTransform.

include/ipatch.h

@@ -215,8 +215,18 @@ class IPatch
     // Reverts any transform that has been applied since the last time freezeTransform() was called
     virtual void revertTransform() = 0;
 
+    // Returns the transformable control point (not the one returned by ctrlAt) - this one is
+    // part of the "transformed" working set of the patch which will either be saved on freezeTransform()
+    // or discarded on revertTransform().
+    virtual PatchControl& getTransformedCtrlAt(std::size_t row, std::size_t col) = 0;
+
     // Promotes the current transformed state to the new base state
     virtual void freezeTransform() = 0;
+
+    // Updates the patch tesselation based on the transformed set of control vertices
+    // Setting force to true will update the tesselation even if controlPointsChanged() 
+    // hasn't been called in the meantime.
+    virtual void updateTesselation(bool force = false) = 0;
 };
 
 namespace patch

radiantcore/patch/Patch.cpp

@@ -406,6 +406,11 @@ const PatchControl& Patch::ctrlAt(std::size_t row, std::size_t col) const {
     return _ctrl[row*_width+col];
 }
 
+PatchControl& Patch::getTransformedCtrlAt(std::size_t row, std::size_t col)
+{
+    return _ctrlTransformed[row * _width + col];
+}
+
 // called just before an action to save the undo state
 void Patch::undoSave()
 {
@@ -518,10 +523,10 @@ bool Patch::isDegenerate() const {
     return true;
 }
 
-void Patch::updateTesselation()
+void Patch::updateTesselation(bool force)
 {
     // Only do something if the tesselation has actually changed
-    if (!_tesselationChanged) return;
+    if (!_tesselationChanged && !force) return;
 
     _tesselationChanged = false;
 

radiantcore/patch/Patch.h

@@ -218,6 +218,8 @@ class Patch :
 	// The same as above just for const
 	const PatchControl& ctrlAt(std::size_t row, std::size_t col) const override;
 
+    PatchControl& getTransformedCtrlAt(std::size_t row, std::size_t col) override;
+
  	/** greebo: Inserts two columns before and after the column with index <colIndex>.
  	 * 			Throws an GenericPatchException if an error occurs.
  	 */
@@ -359,12 +361,12 @@ class Patch :
 	// Static signal holder, signal is emitted after any patch texture has changed
 	static sigc::signal<void>& signal_patchTextureChanged();
 
+    void updateTesselation(bool force = false);
+
 private:
 	// This notifies the surfaceinspector/patchinspector about the texture change
 	void textureChanged();
 
-	void updateTesselation();
-
 	// greebo: checks, if the shader name is valid
 	void check_shader();
 

radiantcore/selection/textool/PatchNode.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "ipatch.h"
+#include "itextstream.h"
 #include "NodeBase.h"
 
 namespace textool
@@ -20,13 +21,15 @@ class PatchNode :
 
     void beginTransformation() override
     {
+        // We call undoSave() here for consistency, but technically it's too early -
+        // the undo operation hasn't started yet
         _patch.undoSave();
     }
 
     void revertTransformation() override
     {
         _patch.revertTransform();
-        _patch.controlPointsChanged();
+        _patch.updateTesselation();
     }
 
     void applyTransformToSelected(const Matrix3& transform) override
@@ -36,11 +39,15 @@ class PatchNode :
             vertex.texcoord = transform * vertex.texcoord;
         });
 
-        _patch.controlPointsChanged();
+        // We have to force the patch to update its tesselation since
+        // modifying the "transformed" control point set won't trigger this
+        _patch.updateTesselation(true);
     }
 
     void commitTransformation() override
     {
+        // Patch::freezeTransform will call undoSave() before overwriting
+        // the control point set with the transformed ones
         _patch.freezeTransform();
     }
 
@@ -118,7 +125,7 @@ class PatchNode :
         {
             for (std::size_t row = 0; row < _patch.getHeight(); ++row)
             {
-                functor(_patch.ctrlAt(row, col));
+                functor(_patch.getTransformedCtrlAt(row, col));
             }
         }
     }