+enum legend_pos{ NORTH = 0, WEST, SOUTH, EAST };
+enum legend_direction { TOP_DOWN = 0, BOTTOM_UP };
+
+enum gfx_if_en { IF_PNG = 0, IF_SVG, IF_EPS, IF_PDF };
+enum gfx_en { GFX_LINE = 0, GFX_AREA, GFX_TEXT };
+enum gfx_h_align_en { GFX_H_NULL = 0, GFX_H_LEFT, GFX_H_RIGHT, GFX_H_CENTER };
+enum gfx_v_align_en { GFX_V_NULL = 0, GFX_V_TOP, GFX_V_BOTTOM, GFX_V_CENTER };
+
+/* cairo color components */
+typedef struct gfx_color_t {
+ double red;
+ double green;
+ double blue;
+ double alpha;
+} gfx_color_t;
+
+