diff --git a/Common/Gfx/Canvas.h b/Common/Gfx/Canvas.h
index 1285d861..f45ab82c 100644
--- a/Common/Gfx/Canvas.h
+++ b/Common/Gfx/Canvas.h
@@ -26,6 +26,7 @@
 
 namespace Gfx {
 
+// Provides methods for drawing text, bitmaps, etc.
 class __declspec(novtable) Canvas
 {
 public:
@@ -34,6 +35,8 @@ public:
 	int GetW() const { return m_W; }
 	int GetH() const { return m_H; }
 
+	// Resize the draw area of the Canvas. This function must not be called if BeginDraw() has been
+	// called and has not yet been matched by a correspoding call to EndDraw.
 	virtual void Resize(int w, int h);
 
 	// BeginDraw() must be matched by a corresponding call to EndDraw(). Drawing functions must be
@@ -54,6 +57,7 @@ public:
 	virtual HDC GetDC() = 0;
 	virtual void ReleaseDC(HDC dc) = 0;
 
+	// The Create* functions allocate objects specific to this Canvas object.
 	virtual FontCollection* CreateFontCollection() = 0;
 	virtual TextFormat* CreateTextFormat() = 0;
 
diff --git a/Common/Gfx/TextFormat.h b/Common/Gfx/TextFormat.h
index 9878e5f0..47082166 100644
--- a/Common/Gfx/TextFormat.h
+++ b/Common/Gfx/TextFormat.h
@@ -39,17 +39,24 @@ enum class VerticalAlignment : BYTE
 	Bottom
 };
 
+// Represents the logical font properties used to format text.
 class __declspec(novtable) TextFormat
 {
 public:
 	virtual ~TextFormat();
 
+	// Returns true if this TextFormat object is valid for use in draw operations.
 	virtual bool IsInitialized() const = 0;
 
+	// Sets the logical properties of the font to use. If the font is not found in the system font
+	// collection, the given |fontCollection| is also searched. |fontCollection| may be nullptr.
 	virtual void SetProperties(
 		const WCHAR* fontFamily, int size, bool bold, bool italic,
 		const FontCollection* fontCollection) = 0;
 
+	// Sets the trimming and wrapping of the text. If |trim| is true, subsequent draws using this
+	// TextFormat object will produce clipped text with an ellipsis if the text overflows the
+	// bounding rectangle. 
 	virtual void SetTrimming(bool trim) = 0;
 
 	virtual void SetHorizontalAlignment(HorizontalAlignment alignment);
diff --git a/Common/Gfx/TextFormatD2D.h b/Common/Gfx/TextFormatD2D.h
index 02cee99b..2c4f292c 100644
--- a/Common/Gfx/TextFormatD2D.h
+++ b/Common/Gfx/TextFormatD2D.h
@@ -25,6 +25,7 @@
 
 namespace Gfx {
 
+// Provides a Direct2D/DirectWrite implementation of TextFormat for use with CanvasD2D.
 class TextFormatD2D : public TextFormat
 {
 public:
@@ -38,6 +39,7 @@ public:
 		const FontCollection* fontCollection) override;
 
 	virtual void SetTrimming(bool trim) override;
+
 	virtual void SetHorizontalAlignment(HorizontalAlignment alignment) override;
 	virtual void SetVerticalAlignment(VerticalAlignment alignment) override;
 
diff --git a/Common/Gfx/TextFormatGDIP.h b/Common/Gfx/TextFormatGDIP.h
index 8e294466..f363204f 100644
--- a/Common/Gfx/TextFormatGDIP.h
+++ b/Common/Gfx/TextFormatGDIP.h
@@ -24,6 +24,7 @@
 
 namespace Gfx {
 
+// Provides a GDI+ implementation of TextFormat for use with CanvasGDIP.
 class TextFormatGDIP : public TextFormat
 {
 public:
@@ -37,6 +38,7 @@ public:
 		const FontCollection* fontCollection) override;
 
 	virtual void SetTrimming(bool trim) override;
+
 	virtual void SetHorizontalAlignment(HorizontalAlignment alignment) override;
 	virtual void SetVerticalAlignment(VerticalAlignment alignment) override;