GFXTransformSaver

Engine/source/gfx/gfxTransformSaver.h

Helper class to store viewport and matrix stack state, and restore it later.

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bool

mHaveSavedData 

bool

mRestoreSavedDataOnDestruct 

MatrixF

mSavedProjectionMatrix 

MatrixF

mSavedViewMatrix 

RectI

mSavedViewport 

GFXTransformSaver(bool saveDataNow, bool restoreDataOnDestruct)

~GFXTransformSaver()

const MatrixF &

getProjectionMatrix()

const MatrixF &

getViewMatrix()

const RectI &

getViewport()

void

restore()

void

save()

Detailed Description

Helper class to store viewport and matrix stack state, and restore it later.

When doing complex out-of-scene rendering, for instance, doing a render to texture operation that needs its own transform state, it is very easy to nuke important rendering state, like the viewport or the projection matrix stored in vertex shader constant zero.

This class simplifies save and cleanup of those properties. You can either treat it as a stack helper, e.g.

void myFunc()
{
   GFXTransformSaver saver;

   // Lots of nasty render state changes...

   // Everything is magically cleaned up when saver is destructed!
}

Or you can manually control when you do saves or restores:

void myFunc()
{
   GFXTransformSaver saver(false, false);

   if(!somePrecondition)
      return false;     // Note early out.

   saver.save();

   // Lots of nasty render state changes...

   // If we had passed (false, true) to the constructor then it would
   // clean up automagically for us; but we want to do it manually.
   saver.restore();
}

bool mHaveSavedData 

bool mRestoreSavedDataOnDestruct 

MatrixF mSavedProjectionMatrix 

MatrixF mSavedViewMatrix 

RectI mSavedViewport 

GFXTransformSaver(bool saveDataNow, bool restoreDataOnDestruct)

~GFXTransformSaver()

getProjectionMatrix()

getViewMatrix()

getViewport()

restore()

save()