sl_type           985 librender/agg/Renderer_agg.cpp typedef agg::scanline_u8_am<agg::alpha_mask_gray8> sl_type;
sl_type          1895 librender/agg/Renderer_agg.cpp typedef agg::scanline_u8_am<agg::alpha_mask_gray8> sl_type; 
sl_type          1905 librender/agg/Renderer_agg.cpp typedef agg::scanline_p8 sl_type; // packed scanline (faster for solid fills)