implement PowerPoint 'flash' slide transition (API CHANGE)

It's like 'fade', but using white instead of black. It's a separate
type in the pptx file (although I actually cannot find it
in the spec OOXML, but PowerPoint 2013 generates it).
The API change in XTransitionFactory should be fine, I doubt
there's anything external using it.

Change-Id: I3479840f265ed8227b3b8301ecff56a63d57f493
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/93668
Tested-by: Luboš Luňák <l.lunak@collabora.com>
Reviewed-by: Luboš Luňák <l.lunak@collabora.com>

3 files changed, 18 insertions, 13 deletions

diff --git a/slideshow/source/engine/opengl/TransitionImpl.cxx b/slideshow/source/engine/opengl/TransitionImpl.cxx
index d1926ab854f9..98d6778fd197 100644
--- a/slideshow/source/engine/opengl/TransitionImpl.cxx
+++ b/slideshow/source/engine/opengl/TransitionImpl.cxx
@@ -1351,37 +1351,40 @@ std::shared_ptr<OGLTransitionImpl> makeFadeSmoothly()
 namespace
 {
 
-class FadeThroughBlackTransition : public OGLTransitionImpl
+class FadeThroughColorTransition : public OGLTransitionImpl
 {
 public:
-    FadeThroughBlackTransition(const TransitionScene& rScene, const TransitionSettings& rSettings)
-        : OGLTransitionImpl(rScene, rSettings)
+    FadeThroughColorTransition(const TransitionScene& rScene, const TransitionSettings& rSettings, bool white)
+        : OGLTransitionImpl(rScene, rSettings), useWhite( white )
     {}
 
 private:
     virtual GLuint makeShader() const override;
+    bool useWhite;
 };
 
-GLuint FadeThroughBlackTransition::makeShader() const
+GLuint FadeThroughColorTransition::makeShader() const
 {
-    return OpenGLHelper::LoadShaders( "basicVertexShader", "fadeBlackFragmentShader" );
+    return OpenGLHelper::LoadShaders( "basicVertexShader", "fadeBlackFragmentShader",
+        useWhite ? "#define use_white" : "", "" );
 }
 
 std::shared_ptr<OGLTransitionImpl>
-makeFadeThroughBlackTransition(
+makeFadeThroughColorTransition(
         const Primitives_t& rLeavingSlidePrimitives,
         const Primitives_t& rEnteringSlidePrimitives,
-        const TransitionSettings& rSettings)
+        const TransitionSettings& rSettings,
+        bool white)
 {
-    return std::make_shared<FadeThroughBlackTransition>(
+    return std::make_shared<FadeThroughColorTransition>(
             TransitionScene(rLeavingSlidePrimitives, rEnteringSlidePrimitives),
-            rSettings)
+            rSettings, white)
         ;
 }
 
 }
 
-std::shared_ptr<OGLTransitionImpl> makeFadeThroughBlack()
+std::shared_ptr<OGLTransitionImpl> makeFadeThroughColor( bool white )
 {
     Primitive Slide;
 
@@ -1395,7 +1398,7 @@ std::shared_ptr<OGLTransitionImpl> makeFadeThroughBlack()
     TransitionSettings aSettings;
     aSettings.mbUseMipMapLeaving = aSettings.mbUseMipMapEntering = false;
 
-    return makeFadeThroughBlackTransition(aLeavingSlide, aEnteringSlide, aSettings);
+    return makeFadeThroughColorTransition(aLeavingSlide, aEnteringSlide, aSettings, white);
 }
 
 namespace
diff --git a/slideshow/source/engine/opengl/TransitionImpl.hxx b/slideshow/source/engine/opengl/TransitionImpl.hxx
index 2831685cd3a7..ca1d36366a6c 100644
--- a/slideshow/source/engine/opengl/TransitionImpl.hxx
+++ b/slideshow/source/engine/opengl/TransitionImpl.hxx
@@ -271,7 +271,8 @@ std::shared_ptr<OGLTransitionImpl> makeNewsflash();
 
 std::shared_ptr<OGLTransitionImpl> makeDiamond();
 std::shared_ptr<OGLTransitionImpl> makeFadeSmoothly();
-std::shared_ptr<OGLTransitionImpl> makeFadeThroughBlack();
+// fade through black or white
+std::shared_ptr<OGLTransitionImpl> makeFadeThroughColor( bool white = false );
 
 class SceneObject
 {
diff --git a/slideshow/source/engine/opengl/TransitionerImpl.cxx b/slideshow/source/engine/opengl/TransitionerImpl.cxx
index 7403cad87425..c60be299752a 100644
--- a/slideshow/source/engine/opengl/TransitionerImpl.cxx
+++ b/slideshow/source/engine/opengl/TransitionerImpl.cxx
@@ -1214,6 +1214,7 @@ public:
     virtual uno::Reference< presentation::XTransition > SAL_CALL createTransition(
         sal_Int16                                             transitionType,
         sal_Int16                                             transitionSubType,
+        sal_Int32                                             transitionFadeColor,
         const uno::Reference< presentation::XSlideShowView >& view,
         const uno::Reference< rendering::XBitmap >&           leavingBitmap,
         const uno::Reference< rendering::XBitmap >&           enteringBitmap ) override
@@ -1288,7 +1289,7 @@ public:
         } else if( transitionType == animations::TransitionType::FADE && transitionSubType == animations::TransitionSubType::CROSSFADE ) {
             pTransition = makeFadeSmoothly();
         } else if( transitionType == animations::TransitionType::FADE && transitionSubType == animations::TransitionSubType::FADEOVERCOLOR ) {
-            pTransition = makeFadeThroughBlack();
+            pTransition = makeFadeThroughColor( transitionFadeColor == 0xffffff );
         } else if( transitionType == animations::TransitionType::IRISWIPE && transitionSubType == animations::TransitionSubType::DIAMOND ) {
             pTransition = makeDiamond();
         } else if( transitionType == animations::TransitionType::ZOOM && transitionSubType == animations::TransitionSubType::ROTATEIN ) {