diff --git a/src/graphics.c b/src/graphics.c
index 9e0b591..011937e 100644
--- a/src/graphics.c
+++ b/src/graphics.c
@@ -22,8 +22,135 @@
 #define LOG_SUBSYSTEM "Graphics"
 
 //------------------------------------------------------------------------
-// graphics handles structs
+// canvas structs
 //------------------------------------------------------------------------
+typedef enum { MG_PATH_MOVE,
+               MG_PATH_LINE,
+	           MG_PATH_QUADRATIC,
+	           MG_PATH_CUBIC } mg_path_elt_type;
+
+typedef struct mg_path_elt
+{
+	mg_path_elt_type type;
+	vec2 p[3];
+
+} mg_path_elt;
+
+typedef struct mg_path_descriptor
+{
+	u32 startIndex;
+	u32 count;
+	vec2 startPoint;
+
+} mg_path_descriptor;
+
+typedef struct mg_attributes
+{
+	f32 width;
+	f32 tolerance;
+	mg_color color;
+	mg_joint_type joint;
+	f32 maxJointExcursion;
+	mg_cap_type cap;
+
+	mg_font font;
+	f32 fontSize;
+
+	mg_image image;
+	mp_rect srcRegion;
+
+	mp_rect clip;
+
+} mg_attributes;
+
+typedef struct mg_rounded_rect
+{
+	f32 x;
+	f32 y;
+	f32 w;
+	f32 h;
+	f32 r;
+} mg_rounded_rect;
+
+typedef enum { MG_CMD_CLEAR = 0,
+	       MG_CMD_FILL,
+	       MG_CMD_STROKE,
+	       MG_CMD_RECT_FILL,
+	       MG_CMD_RECT_STROKE,
+	       MG_CMD_ROUND_RECT_FILL,
+	       MG_CMD_ROUND_RECT_STROKE,
+	       MG_CMD_ELLIPSE_FILL,
+	       MG_CMD_ELLIPSE_STROKE,
+	       MG_CMD_JUMP,
+	       MG_CMD_CLIP_PUSH,
+	       MG_CMD_CLIP_POP,
+	     } mg_primitive_cmd;
+
+typedef struct mg_primitive
+{
+	mg_primitive_cmd cmd;
+	mg_attributes attributes;
+	mg_mat2x3 transform;
+
+	union
+	{
+		mg_path_descriptor path;
+		mp_rect rect;
+		mg_rounded_rect roundedRect;
+		utf32 codePoint;
+		u32 jump;
+		mg_mat2x3 matrix; //TODO remove when we use transform everywhere
+	};
+
+} mg_primitive;
+
+typedef struct mg_glyph_map_entry
+{
+	unicode_range range;
+	u32 firstGlyphIndex;
+
+} mg_glyph_map_entry;
+
+typedef struct mg_glyph_data
+{
+	bool exists;
+	utf32 codePoint;
+	mg_path_descriptor pathDescriptor;
+	mg_text_extents extents;
+	//...
+
+} mg_glyph_data;
+
+enum
+{
+	MG_STREAM_MAX_COUNT = 128,
+	MG_IMAGE_MAX_COUNT = 128
+};
+
+enum
+{
+	MG_MATRIX_STACK_MAX_DEPTH = 64,
+	MG_CLIP_STACK_MAX_DEPTH = 64,
+	MG_MAX_PATH_ELEMENT_COUNT = 2<<20,
+	MG_MAX_PRIMITIVE_COUNT = 8<<10
+};
+
+typedef struct mg_font_data
+{
+	list_elt freeListElt;
+	u32 generation;
+
+	u32 rangeCount;
+	u32 glyphCount;
+	u32 outlineCount;
+	mg_glyph_map_entry* glyphMap;
+	mg_glyph_data*      glyphs;
+	mg_path_elt* outlines;
+
+	f32 unitsPerEm;
+	mg_font_extents extents;
+
+} mg_font_data;
 
 typedef struct mg_canvas_data mg_canvas_data;
 
@@ -113,12 +240,6 @@ typedef struct mg_canvas_data
 
 } mg_canvas_data;
 
-enum
-{
-	MG_ATLAS_SIZE = 8192,
-};
-
-
 static mg_data __mgData = {0};
 
 
diff --git a/src/graphics_internal.h b/src/graphics_internal.h
index 8191e3e..387b9c1 100644
--- a/src/graphics_internal.h
+++ b/src/graphics_internal.h
@@ -16,7 +16,7 @@ extern "C" {
 #endif
 
 //---------------------------------------------------------------
-// surface data
+// surface interface
 //---------------------------------------------------------------
 typedef struct mg_surface_data mg_surface_data;
 
@@ -50,111 +50,8 @@ mg_surface mg_surface_alloc_handle(mg_surface_data* surface);
 mg_surface_data* mg_surface_data_from_handle(mg_surface handle);
 
 //---------------------------------------------------------------
-// graphics structs
+// canvas backend interface
 //---------------------------------------------------------------
-typedef enum { MG_PATH_MOVE,
-               MG_PATH_LINE,
-	           MG_PATH_QUADRATIC,
-	           MG_PATH_CUBIC } mg_path_elt_type;
-
-typedef struct mg_path_elt
-{
-	mg_path_elt_type type;
-	vec2 p[3];
-
-} mg_path_elt;
-
-typedef struct mg_path_descriptor
-{
-	u32 startIndex;
-	u32 count;
-	vec2 startPoint;
-
-} mg_path_descriptor;
-
-typedef struct mg_attributes
-{
-	f32 width;
-	f32 tolerance;
-	mg_color color;
-	mg_joint_type joint;
-	f32 maxJointExcursion;
-	mg_cap_type cap;
-
-	mg_font font;
-	f32 fontSize;
-
-	mg_image image;
-	mp_rect srcRegion;
-
-	mp_rect clip;
-
-} mg_attributes;
-
-typedef struct mg_rounded_rect
-{
-	f32 x;
-	f32 y;
-	f32 w;
-	f32 h;
-	f32 r;
-} mg_rounded_rect;
-
-typedef enum { MG_CMD_CLEAR = 0,
-	       MG_CMD_FILL,
-	       MG_CMD_STROKE,
-	       MG_CMD_RECT_FILL,
-	       MG_CMD_RECT_STROKE,
-	       MG_CMD_ROUND_RECT_FILL,
-	       MG_CMD_ROUND_RECT_STROKE,
-	       MG_CMD_ELLIPSE_FILL,
-	       MG_CMD_ELLIPSE_STROKE,
-	       MG_CMD_JUMP,
-	       MG_CMD_CLIP_PUSH,
-	       MG_CMD_CLIP_POP,
-	     } mg_primitive_cmd;
-
-typedef struct mg_primitive
-{
-	mg_primitive_cmd cmd;
-	mg_attributes attributes;
-	mg_mat2x3 transform;
-
-	union
-	{
-		mg_path_descriptor path;
-		mp_rect rect;
-		mg_rounded_rect roundedRect;
-		utf32 codePoint;
-		u32 jump;
-		mg_mat2x3 matrix; //TODO remove when we use transform everywhere
-	};
-
-} mg_primitive;
-
-typedef struct mg_glyph_map_entry
-{
-	unicode_range range;
-	u32 firstGlyphIndex;
-
-} mg_glyph_map_entry;
-
-typedef struct mg_glyph_data
-{
-	bool exists;
-	utf32 codePoint;
-	mg_path_descriptor pathDescriptor;
-	mg_text_extents extents;
-	//...
-
-} mg_glyph_data;
-
-enum
-{
-	MG_STREAM_MAX_COUNT = 128,
-	MG_IMAGE_MAX_COUNT = 128
-};
-
 typedef struct mg_image_data
 {
 	list_elt listElt;
@@ -163,31 +60,6 @@ typedef struct mg_image_data
 
 } mg_image_data;
 
-enum
-{
-	MG_MATRIX_STACK_MAX_DEPTH = 64,
-	MG_CLIP_STACK_MAX_DEPTH = 64,
-	MG_MAX_PATH_ELEMENT_COUNT = 2<<20,
-	MG_MAX_PRIMITIVE_COUNT = 8<<10
-};
-
-typedef struct mg_font_data
-{
-	list_elt freeListElt;
-	u32 generation;
-
-	u32 rangeCount;
-	u32 glyphCount;
-	u32 outlineCount;
-	mg_glyph_map_entry* glyphMap;
-	mg_glyph_data*      glyphs;
-	mg_path_elt* outlines;
-
-	f32 unitsPerEm;
-	mg_font_extents extents;
-
-} mg_font_data;
-
 typedef struct mg_vertex_layout
 {
 	u32 maxVertexCount;