AGG lesson 29 the difference of agg::render_scanlines

Attach the code:

Agg::rendering_buffer & rbuf = rbuf_window (); / / get the rendering cache

Agg::pixfmt_bgr24 pixf (rbuf); / / make up pixels

Typedef agg::renderer_base renderer_base_type

Renderer_base_type renb (pixf); / / provides a crop region, which is valid for rendering only within the crop region

Typedef agg::renderer_scanline_bin_solid renderder_scanline_type

Renderder_scanline_type rensl (renb); / / customize the underlying renderer

Agg::rasterizer_scanline_aa ras

Agg::scanline_u8 sl

Ras.reset ()

Renb.clear (agg::rgba8 (255255255))

Agg::ellipse ell (320230230)

Agg::conv_stroke stroke (ell)

Ras.add_path (stroke)

Rensl.color (agg::rgba8 (255j0pl 0))

Agg::render_scanlines (ras,sl,rensl)

This method does not provide anti-aliasing effect, using agg::renderer_scanline_bin_solid

Compare the following code:

Agg::rendering_buffer & rbuf = rbuf_window ()

Agg::pixfmt_bgr24 pixf (rbuf)

Typedef agg::renderer_base renderer_base_type

Renderer_base_type renb (pixf)

Renb.clear (agg::rgba8 (255255255))

Agg::rasterizer_scanline_aa ras

Agg::scanline_u8 sl

Ren_bas.clear (agg::rgba8 (255255255))

Agg::ellipse ell (320230230)

Agg::conv_stroke stroke (ell)

Ras.add_path (stroke)

Agg::render_scanlines_aa_solid (ras,sl,renb,agg::rgba8 (255j0pl 0))

The rendered circle is anti-aliased and the effect is very good. Aa actually means anti-aliasing.