added optimization so that as we render top->bottom, if the clip region ever

becomes empty, we stop rendering.
1998-06-03 21:30:51 +00:00 · 1998-06-03 21:30:51 +00:00 · 49c4d29e3f
--- a/gfx/src/motif/nsRenderingContextUnix.cpp
+++ b/gfx/src/motif/nsRenderingContextUnix.cpp
@ -111,8 +111,9 @@ PRBool nsRenderingContextUnix :: IsVisibleRect(const nsRect& aRect)
  return PR_TRUE;
 }

-void nsRenderingContextUnix :: SetClipRect(const nsRect& aRect, nsClipCombine aCombine)
+PRBool nsRenderingContextUnix :: SetClipRect(const nsRect& aRect, nsClipCombine aCombine)
 {
+  return PR_FALSE;
 }

 PRBool nsRenderingContextUnix :: GetClipRect(nsRect &aRect)
@ -120,9 +121,10 @@ PRBool nsRenderingContextUnix :: GetClipRect(nsRect &aRect)
  return PR_FALSE;
 }

-void nsRenderingContextUnix :: SetClipRegion(const nsIRegion& aRegion, nsClipCombine aCombine)
+PRBool nsRenderingContextUnix :: SetClipRegion(const nsIRegion& aRegion, nsClipCombine aCombine)
 {
  //XXX wow, needs to do something.
+  return PR_FALSE;
 }

 void nsRenderingContextUnix :: GetClipRegion(nsIRegion **aRegion)
--- a/gfx/src/motif/nsRenderingContextUnix.h
+++ b/gfx/src/motif/nsRenderingContextUnix.h
@ -68,9 +68,9 @@ public:

  virtual PRBool IsVisibleRect(const nsRect& aRect);

-  virtual void SetClipRect(const nsRect& aRect, nsClipCombine aCombine);
+  virtual PRBool SetClipRect(const nsRect& aRect, nsClipCombine aCombine);
  virtual PRBool GetClipRect(nsRect &aRect);
-  virtual void SetClipRegion(const nsIRegion& aRegion, nsClipCombine aCombine);
+  virtual PRBool SetClipRegion(const nsIRegion& aRegion, nsClipCombine aCombine);
  virtual void GetClipRegion(nsIRegion **aRegion);

  virtual void SetColor(nscolor aColor);
--- a/gfx/src/nsIRenderingContext.h
+++ b/gfx/src/nsIRenderingContext.h
@ -119,15 +119,16 @@ public:
   * @param aRect The rectangle to set the clipping rectangle to
   * @param aCombine how to combine this rect with the current clip region.
   *        see the bottom of nsIRenderingContext.h
+   * @return PR_TRUE if the clip region is now empty, else PR_FALSE
   */
-  virtual void SetClipRect(const nsRect& aRect, nsClipCombine aCombine) = 0;
+  virtual PRBool SetClipRect(const nsRect& aRect, nsClipCombine aCombine) = 0;

  /**
   * Gets the bounds of the clip region of the RenderingContext
   * @param aRect out parameter to contain the clip region bounds
   *        for the RenderingContext
-   * @return PR_TRUE if the rendering context has a cliprect set
-   *         (i.e. this is the exact clip rect, not a clip region bounds)
+   * @return PR_TRUE if the rendering context has a local cliprect set
+   *         else aRect is undefined
   */
  virtual PRBool GetClipRect(nsRect &aRect) = 0;

@ -136,8 +137,9 @@ public:
   * @param aRegion The region to set the clipping area to
   * @param aCombine how to combine this region with the current clip region.
   *        see the bottom of nsIRenderingContext.h
+   * @return PR_TRUE if the clip region is now empty, else PR_FALSE
   */
-  virtual void SetClipRegion(const nsIRegion& aRegion, nsClipCombine aCombine) = 0;
+  virtual PRBool SetClipRegion(const nsIRegion& aRegion, nsClipCombine aCombine) = 0;

  /**
   * Gets the current clipping region for the RenderingContext
--- a/gfx/src/windows/nsRenderingContextWin.cpp
+++ b/gfx/src/windows/nsRenderingContextWin.cpp
@ -402,9 +402,10 @@ PRBool nsRenderingContextWin :: IsVisibleRect(const nsRect& aRect)
  return PR_TRUE;
 }

-void nsRenderingContextWin :: SetClipRect(const nsRect& aRect, nsClipCombine aCombine)
+PRBool nsRenderingContextWin :: SetClipRect(const nsRect& aRect, nsClipCombine aCombine)
 {
  nsRect  trect = aRect;
+  int     cliptype;

  mStates->mLocalClip = aRect;

@ -419,10 +420,10 @@ void nsRenderingContextWin :: SetClipRect(const nsRect& aRect, nsClipCombine aCo
  {
    PushClipState();

-    ::IntersectClipRect(mDC, trect.x,
-                             trect.y,
-                             trect.XMost(),
-                             trect.YMost());
+    cliptype = ::IntersectClipRect(mDC, trect.x,
+                                   trect.y,
+                                   trect.XMost(),
+                                   trect.YMost());
  }
  else if (aCombine == nsClipCombine_kUnion)
  {
@ -433,17 +434,17 @@ void nsRenderingContextWin :: SetClipRect(const nsRect& aRect, nsClipCombine aCo
                                    trect.XMost(),
                                    trect.YMost());

-    ::ExtSelectClipRgn(mDC, tregion, RGN_OR);
+    cliptype = ::ExtSelectClipRgn(mDC, tregion, RGN_OR);
    ::DeleteObject(tregion);
  }
  else if (aCombine == nsClipCombine_kSubtract)
  {
    PushClipState();

-    ::ExcludeClipRect(mDC, trect.x,
-                           trect.y,
-                           trect.XMost(),
-                           trect.YMost());
+    cliptype = ::ExcludeClipRect(mDC, trect.x,
+                                 trect.y,
+                                 trect.XMost(),
+                                 trect.YMost());
  }
  else if (aCombine == nsClipCombine_kReplace)
  {
@ -453,11 +454,16 @@ void nsRenderingContextWin :: SetClipRect(const nsRect& aRect, nsClipCombine aCo
                                    trect.y,
                                    trect.XMost(),
                                    trect.YMost());
-    ::SelectClipRgn(mDC, tregion);
+    cliptype = ::SelectClipRgn(mDC, tregion);
    ::DeleteObject(tregion);
  }
  else
    NS_ASSERTION(FALSE, "illegal clip combination");
+
+  if (cliptype == NULLREGION)
+    return PR_TRUE;
+  else
+    return PR_FALSE;
 }

 PRBool nsRenderingContextWin :: GetClipRect(nsRect &aRect)
@ -471,11 +477,11 @@ PRBool nsRenderingContextWin :: GetClipRect(nsRect &aRect)
    return PR_FALSE;
 }

-void nsRenderingContextWin :: SetClipRegion(const nsIRegion& aRegion, nsClipCombine aCombine)
+PRBool nsRenderingContextWin :: SetClipRegion(const nsIRegion& aRegion, nsClipCombine aCombine)
 {
  nsRegionWin *pRegion = (nsRegionWin *)&aRegion;
-  HRGN hrgn = pRegion->GetHRGN();
-  int cmode;
+  HRGN        hrgn = pRegion->GetHRGN();
+  int         cmode, cliptype;

  switch (aCombine)
  {
@ -501,8 +507,15 @@ void nsRenderingContextWin :: SetClipRegion(const nsIRegion& aRegion, nsClipComb
  {
    mStates->mFlags &= ~FLAG_LOCAL_CLIP_VALID;
    PushClipState();
-    ::ExtSelectClipRgn(mDC, hrgn, cmode);
+    cliptype = ::ExtSelectClipRgn(mDC, hrgn, cmode);
  }
+  else
+    return PR_FALSE;
+
+  if (cliptype == NULLREGION)
+    return PR_TRUE;
+  else
+    return PR_FALSE;
 }

 void nsRenderingContextWin :: GetClipRegion(nsIRegion **aRegion)
--- a/gfx/src/windows/nsRenderingContextWin.h
+++ b/gfx/src/windows/nsRenderingContextWin.h
@ -65,9 +65,9 @@ public:

  virtual PRBool IsVisibleRect(const nsRect& aRect);

-  virtual void SetClipRect(const nsRect& aRect, nsClipCombine aCombine);
+  virtual PRBool SetClipRect(const nsRect& aRect, nsClipCombine aCombine);
  virtual PRBool GetClipRect(nsRect &aRect);
-  virtual void SetClipRegion(const nsIRegion& aRegion, nsClipCombine aCombine);
+  virtual PRBool SetClipRegion(const nsIRegion& aRegion, nsClipCombine aCombine);
  virtual void GetClipRegion(nsIRegion **aRegion);

  virtual void SetColor(nscolor aColor);
--- a/view/public/nsIView.h
+++ b/view/public/nsIView.h
@ -126,9 +126,10 @@ public:
   * @param aBackstop if we will need to do back to front
   *        painting, this is the view that, once rendered
   *        ends the back to front pass.
+   * @return PR_TRUE if the entire clip region has been eliminated, else PR_FALSE
   */
-  virtual void Paint(nsIRenderingContext& rc, const nsRect& rect,
-                     PRUint32 aPaintFlags, nsIView *aBackstop = nsnull) = 0;
+  virtual PRBool Paint(nsIRenderingContext& rc, const nsRect& rect,
+                       PRUint32 aPaintFlags, nsIView *aBackstop = nsnull) = 0;

  /**
   * Called to indicate that the specified region of the view
@ -137,8 +138,9 @@ public:
   * @param rc rendering context to paint into
   * @param region damage area
   * @param aPaintFlags see nsIView.h for flag definitions
+   * @return PR_TRUE if the entire clip region has been eliminated, else PR_FALSE
   */
-  virtual void Paint(nsIRenderingContext& rc, const nsIRegion& region, PRUint32 aPaintFlags) = 0;
+  virtual PRBool Paint(nsIRenderingContext& rc, const nsIRegion& region, PRUint32 aPaintFlags) = 0;
  
  /**
   * Called to indicate that the specified event should be handled
--- a/view/src/nsView.cpp
+++ b/view/src/nsView.cpp
@ -373,10 +373,11 @@ nsIWidget * nsView :: GetWidget()
  return mWindow;
 }

-void nsView :: Paint(nsIRenderingContext& rc, const nsRect& rect,
-                     PRUint32 aPaintFlags, nsIView *aBackstop)
+PRBool nsView :: Paint(nsIRenderingContext& rc, const nsRect& rect,
+                       PRUint32 aPaintFlags, nsIView *aBackstop)
 {
  nsIView *pRoot = mViewManager->GetRootView();
+  PRBool  clipres = PR_FALSE;

  rc.PushState();

@ -389,52 +390,62 @@ void nsView :: Paint(nsIRenderingContext& rc, const nsRect& rect,
    crect.width = mClip.mRight - mClip.mLeft;
    crect.height = mClip.mBottom - mClip.mTop;

-    rc.SetClipRect(crect, nsClipCombine_kIntersect);
+    clipres = rc.SetClipRect(crect, nsClipCombine_kIntersect);
  }
  else if (this != pRoot)
-    rc.SetClipRect(mBounds, nsClipCombine_kIntersect);
+    clipres = rc.SetClipRect(mBounds, nsClipCombine_kIntersect);

-  rc.Translate(mBounds.x, mBounds.y);
-
-  //XXX maybe we should set this before we set the clip? MMP
-
-  if (nsnull != mXForm)
+  if (clipres == PR_FALSE)
  {
-    nsTransform2D *pXForm = rc.GetCurrentTransform();
-    pXForm->Concatenate(mXForm);
-  }
+    rc.Translate(mBounds.x, mBounds.y);

-  PRInt32 numkids = GetChildCount();
+    //XXX maybe we should set this before we set the clip? MMP

-  for (PRInt32 cnt = 0; cnt < numkids; cnt++)
-  {
-    nsIView *kid = GetChild(cnt);
-
-    if (nsnull != kid)
+    if (nsnull != mXForm)
    {
-      nsRect kidRect;
-      kid->GetBounds(kidRect);
-      nsRect damageArea;
-      PRBool overlap = damageArea.IntersectRect(rect, kidRect);
+      nsTransform2D *pXForm = rc.GetCurrentTransform();
+      pXForm->Concatenate(mXForm);
+    }

-      if (overlap == PR_TRUE)
+    PRInt32 numkids = GetChildCount();
+
+    for (PRInt32 cnt = 0; cnt < numkids; cnt++)
+    {
+      nsIView *kid = GetChild(cnt);
+
+      if (nsnull != kid)
      {
-        // Translate damage area into kid's coordinate system
-        nsRect kidDamageArea(damageArea.x - kidRect.x, damageArea.y - kidRect.y,
-                             damageArea.width, damageArea.height);
-        kid->Paint(rc, kidDamageArea, aPaintFlags);
+        nsRect kidRect;
+        kid->GetBounds(kidRect);
+        nsRect damageArea;
+        PRBool overlap = damageArea.IntersectRect(rect, kidRect);
+
+        if (overlap == PR_TRUE)
+        {
+          // Translate damage area into kid's coordinate system
+          nsRect kidDamageArea(damageArea.x - kidRect.x, damageArea.y - kidRect.y,
+                               damageArea.width, damageArea.height);
+          clipres = kid->Paint(rc, kidDamageArea, aPaintFlags);
+
+          if (clipres == PR_TRUE)
+            break;
+        }
      }
    }
+
+    if ((clipres == PR_FALSE) && (mVis == nsViewVisibility_kShow) && (nsnull != mFrame))
+    {
+      nsIPresContext  *cx = mViewManager->GetPresContext();
+      rc.PushState();
+      mFrame->Paint(*cx, rc, rect);
+      rc.PopState();
+      NS_RELEASE(cx);
+    }
  }

-  if ((mVis == nsViewVisibility_kShow) && (nsnull != mFrame))
-  {
-    nsIPresContext  *cx = mViewManager->GetPresContext();
-    rc.PushState();
-    mFrame->Paint(*cx, rc, rect);
-    rc.PopState();
-    NS_RELEASE(cx);
-  }
+  //XXX would be nice if we could have a version of pop that just removes the
+  //state from the stack but doesn't change the state of the underlying graphics
+  //context. MMP

  rc.PopState();

@ -442,7 +453,7 @@ void nsView :: Paint(nsIRenderingContext& rc, const nsRect& rect,
  //paint process. only do this if this view is actually
  //visible and if there is no widget (like a scrollbar) here.

-  if ((mVis == nsViewVisibility_kShow) && (nsnull == mWindow))
+  if ((clipres == PR_FALSE) && (mVis == nsViewVisibility_kShow) && (nsnull == mWindow))
  {
    if ((mClip.mLeft != mClip.mRight) && (mClip.mTop != mClip.mBottom))
    {
@ -453,21 +464,24 @@ void nsView :: Paint(nsIRenderingContext& rc, const nsRect& rect,
      crect.width = mClip.mRight - mClip.mLeft;
      crect.height = mClip.mBottom - mClip.mTop;

-      rc.SetClipRect(crect, nsClipCombine_kSubtract);
+      clipres = rc.SetClipRect(crect, nsClipCombine_kSubtract);
    }
    else if (this != pRoot)
-      rc.SetClipRect(mBounds, nsClipCombine_kSubtract);
+      clipres = rc.SetClipRect(mBounds, nsClipCombine_kSubtract);
  }

  NS_RELEASE(pRoot);
+
+  return clipres;
 }

-void nsView :: Paint(nsIRenderingContext& rc, const nsIRegion& region, PRUint32 aPaintFlags)
+PRBool nsView :: Paint(nsIRenderingContext& rc, const nsIRegion& region, PRUint32 aPaintFlags)
 {
  // XXX apply region to rc
  // XXX get bounding rect from region
  //if (nsnull != mFrame)
  //  mFrame->Paint(rc, rect, aPaintFlags);
+  return PR_FALSE;
 }

 nsEventStatus nsView :: HandleEvent(nsGUIEvent *event, PRUint32 aEventFlags)
--- a/view/src/nsView.h
+++ b/view/src/nsView.h
@ -56,9 +56,9 @@ public:
  virtual void Destroy();
  virtual nsIViewManager * GetViewManager();
  virtual nsIWidget * GetWidget();
-  virtual void Paint(nsIRenderingContext& rc, const nsRect& rect,
+  virtual PRBool Paint(nsIRenderingContext& rc, const nsRect& rect,
                     PRUint32 aPaintFlags, nsIView *aBackstop = nsnull);
-  virtual void Paint(nsIRenderingContext& rc, const nsIRegion& region, PRUint32 aPaintFlags);
+  virtual PRBool Paint(nsIRenderingContext& rc, const nsIRegion& region, PRUint32 aPaintFlags);
  virtual nsEventStatus HandleEvent(nsGUIEvent *event, PRUint32 aEventFlags);
  virtual void SetPosition(nscoord x, nscoord y);
  virtual void GetPosition(nscoord *x, nscoord *y);