added tracking the usage of the special B_OP_COPY version for text

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@17326 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/servers/app/drawing/Painter/drawing_modes/PixelFormat.cpp

@@ -108,6 +108,7 @@ PixelFormat::PixelFormat(agg::rendering_buffer& rb,
 						 const PatternHandler* handler)
 	: fBuffer(&rb),
 	  fPatternHandler(handler),
+	  fUsesOpCopyForText(false),
 
 	  fBlendPixel(blend_pixel_empty),
 	  fBlendHLine(blend_hline_empty),
@@ -129,6 +130,7 @@ void
 PixelFormat::SetDrawingMode(drawing_mode mode, source_alpha alphaSrcMode,
 							alpha_function alphaFncMode, bool text)
 {
+	fUsesOpCopyForText = false;
 	switch (mode) {
 		// these drawing modes discard source pixels
 		// which have the current low color
@@ -178,6 +180,10 @@ PixelFormat::SetDrawingMode(drawing_mode mode, source_alpha alphaSrcMode,
 				fBlendSolidHSpan = blend_solid_hspan_copy_text;
 				fBlendSolidVSpan = blend_solid_vspan_copy_text;
 				fBlendColorHSpan = blend_color_hspan_copy_text;
+				// set the special flag so that Painter
+				// knows if an update is needed even though
+				// "nothing changed"
+				fUsesOpCopyForText = true;
 			} else if (fPatternHandler->IsSolid()) {
 				fBlendPixel = blend_pixel_copy_solid;
 				fBlendHLine = blend_hline_copy_solid;

src/servers/app/drawing/Painter/drawing_modes/PixelFormat.h

@@ -61,6 +61,9 @@ class PixelFormat {
 											   alpha_function alphaFncMode,
 											   bool text);
 
+	inline	bool				UsesOpCopyForText() const
+									{ return fUsesOpCopyForText; }
+
 			// AGG "pixel format" interface
 			unsigned			width()  const { return fBuffer->width();  }
 			unsigned			height() const { return fBuffer->height(); }
@@ -105,6 +108,7 @@ class PixelFormat {
  private:
 	agg::rendering_buffer*		fBuffer;
 	const PatternHandler*		fPatternHandler;
+	bool						fUsesOpCopyForText;
 
 	blend_pixel_f				fBlendPixel;
 	blend_line					fBlendHLine;