Fix behaviour when PreeditStyle is REVERSE

[platform/core/uifw/dali-toolkit.git] / dali-toolkit / internal / text / text-controller-impl.cpp

diff --git a/dali-toolkit/internal/text/text-controller-impl.cpp b/dali-toolkit/internal/text/text-controller-impl.cpp
index b8b6f31..12cdae7 100644 (file)
--- a/dali-toolkit/internal/text/text-controller-impl.cpp
+++ b/dali-toolkit/internal/text/text-controller-impl.cpp
@@ -35,11 +35,11 @@
 #include <dali-toolkit/internal/text/shaper.h>
 #include <dali-toolkit/internal/text/text-control-interface.h>
 #include <dali-toolkit/internal/text/text-controller-impl-event-handler.h>
+#include <dali-toolkit/internal/text/text-editable-control-interface.h>
+#include <dali-toolkit/internal/text/text-enumerations-impl.h>
 #include <dali-toolkit/internal/text/text-run-container.h>
 #include <dali-toolkit/internal/text/text-selection-handle-controller.h>
 
-#include <dali-toolkit/internal/text/text-enumerations-impl.h>
-
 using namespace Dali;
 
 namespace
@@ -60,6 +60,14 @@ struct BackgroundMesh
   Vector<unsigned short>   mIndices;  ///< container of indices
 };
 
+// The relative luminance of a color is defined as (L = 0.2126 * R + 0.7152 * G + 0.0722 * B)
+// based on W3C Recommendations (https://www.w3.org/TR/WCAG20/)
+const float         BRIGHTNESS_THRESHOLD = 0.179f;
+const float         CONSTANT_R           = 0.2126f;
+const float         CONSTANT_G           = 0.7152f;
+const float         CONSTANT_B           = 0.0722f;
+const Dali::Vector4 BLACK(0.f, 0.f, 0.f, 1.f);
+const Dali::Vector4 WHITE(1.f, 1.f, 1.f, 1.f);
 const Dali::Vector4 LIGHT_BLUE(0.75f, 0.96f, 1.f, 1.f);
 const Dali::Vector4 BACKGROUND_SUB4(0.58f, 0.87f, 0.96f, 1.f);
 const Dali::Vector4 BACKGROUND_SUB5(0.83f, 0.94f, 0.98f, 1.f);
@@ -915,7 +923,23 @@ bool Controller::Impl::UpdateModel(OperationsMask operationsRequired)
           backgroundColorRun.color                           = textColor;
           mModel->mLogicalModel->mBackgroundColorRuns.PushBack(backgroundColorRun);
 
-          Vector4          backgroundColor = mModel->mVisualModel->GetBackgroundColor();
+          Vector4 backgroundColor = mModel->mVisualModel->GetBackgroundColor();
+          if(backgroundColor.a == 0) // There is no text background color.
+          {
+            // Try use the control's background color.
+            if(nullptr != mEditableControlInterface)
+            {
+              mEditableControlInterface->GetControlBackgroundColor(backgroundColor);
+              if(backgroundColor.a == 0) // There is no control background color.
+              {
+                // Determines black or white color according to text color.
+                // Based on W3C Recommendations (https://www.w3.org/TR/WCAG20/)
+                float L         = CONSTANT_R * textColor.r + CONSTANT_G * textColor.g + CONSTANT_B * textColor.b;
+                backgroundColor = L > BRIGHTNESS_THRESHOLD ? BLACK : WHITE;
+              }
+            }
+          }
+
           Vector<ColorRun> colorRuns;
           colorRuns.Resize(1u);
           ColorRun& colorRun                       = *(colorRuns.Begin());