* added a little documentation to BIconUtils in the header

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@18401 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/libs/icon/IconUtils.cpp

@@ -96,7 +96,7 @@ BIconUtils::GetVectorIcon(const uint8* buffer, size_t size,
 	renderer.Render();
 
 	// TODO: would be nice to get rid of this
-	// (B_RGBA32_PREMULTIPLIED or better yes, new blending_mode)
+	// (B_RGBA32_PREMULTIPLIED or better yet, new blending_mode)
 	// NOTE: probably not necessary only because
 	// transparent colors are "black" in all existing icons
 	// lighter transparent colors should be too dark if
@@ -106,6 +106,8 @@ BIconUtils::GetVectorIcon(const uint8* buffer, size_t size,
 	return B_OK;
 }
 
+// #pragma mark -
+
 // ConvertFromCMAP8
 status_t
 BIconUtils::ConvertFromCMAP8(BBitmap* source, BBitmap* result)
@@ -117,6 +119,9 @@ BIconUtils::ConvertFromCMAP8(BBitmap* source, BBitmap* result)
 	if (ret < B_OK)
 		return ret;
 
+	if (source->ColorSpace() != B_CMAP8)
+		return B_BAD_VALUE;
+
 	uint8* src = (uint8*)source->Bits();
 	uint32 srcBPR = source->BytesPerRow();
 	uint32 width = source->Bounds().IntegerWidth() + 1;

src/libs/icon/IconUtils.h

@@ -23,6 +23,15 @@ class BIconUtils {
 
  public:
 
+	// Utility functions to import a vector icon in "flat icon"
+	// format from a BNode attribute or from a flat buffer in
+	// memory into the preallocated BBitmap "result".
+	// The colorspace of result needs to be B_RGBA32 or at
+	// least B_RGB32 (though that makes less sense). The icon
+	// will be scaled from it's "native" size of 64x64 to the
+	// size of the bitmap, the scale is derived from the bitmap
+	// width, the bitmap should have square dimension, or the
+	// icon will be cut off at the bottom (or have room left).
 	static	status_t			GetVectorIcon(BNode* node,
 											  const char* attrName,
 											  BBitmap* result);
@@ -32,6 +41,9 @@ class BIconUtils {
 											  BBitmap* result);
 
 
+	// Utility functions to convert from old icon colorspace
+	// into colorspace of BBitmap "result" (should be B_RGBA32
+	// to make any sense).
 	static	status_t			ConvertFromCMAP8(BBitmap* source,
 												 BBitmap* result);