1 2 //---------------------------------------------------------------------------- 3 // Anti-Grain Geometry - Version 2.3 4 // Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com) 5 // 6 // Permission to copy, use, modify, sell and distribute this software 7 // is granted provided this copyright notice appears in all copies. 8 // This software is provided "as is" without express or implied 9 // warranty, and with no claim as to its suitability for any purpose. 10 // 11 //---------------------------------------------------------------------------- 12 // Contact: mcseem@antigrain.com 13 // mcseemagg@yahoo.com 14 // http://www.antigrain.com 15 //---------------------------------------------------------------------------- 16 #ifndef AGG_RENDERER_SCANLINE_INCLUDED 17 #define AGG_RENDERER_SCANLINE_INCLUDED 18 #include "agg_basics.h" 19 #include "agg_renderer_base.h" 20 #include "agg_render_scanlines.h" 21 namespace agg 22 { 23 template<class BaseRenderer, class SpanGenerator> class renderer_scanline_aa 24 { 25 public: 26 typedef BaseRenderer base_ren_type; 27 typedef SpanGenerator span_gen_type; renderer_scanline_aa()28 renderer_scanline_aa() : m_ren(0), m_span_gen(0) {} renderer_scanline_aa(base_ren_type & ren,span_gen_type & span_gen)29 renderer_scanline_aa(base_ren_type& ren, span_gen_type& span_gen) : 30 m_ren(&ren), 31 m_span_gen(&span_gen) 32 {} attach(base_ren_type & ren,span_gen_type & span_gen)33 void attach(base_ren_type& ren, span_gen_type& span_gen) 34 { 35 m_ren = &ren; 36 m_span_gen = &span_gen; 37 } prepare(unsigned max_span_len)38 void prepare(unsigned max_span_len) 39 { 40 m_span_gen->prepare(max_span_len); 41 } render(const Scanline & sl)42 template<class Scanline> void render(const Scanline& sl) 43 { 44 int y = sl.y(); 45 m_ren->first_clip_box(); 46 do { 47 int xmin = m_ren->xmin(); 48 int xmax = m_ren->xmax(); 49 if(y >= m_ren->ymin() && y <= m_ren->ymax()) { 50 unsigned num_spans = sl.num_spans(); 51 typename Scanline::const_iterator span = sl.begin(); 52 for(;;) { 53 int x = span->x; 54 int len = span->len; 55 bool solid = false; 56 const typename Scanline::cover_type* covers = span->covers; 57 if(len < 0) { 58 solid = true; 59 len = -len; 60 } 61 if(x < xmin) { 62 len -= xmin - x; 63 if(!solid) { 64 covers += xmin - x; 65 } 66 x = xmin; 67 } 68 if(len > 0) { 69 if(x + len > xmax) { 70 len = xmax - x + 1; 71 } 72 if(len > 0) { 73 m_ren->blend_color_hspan_no_clip( 74 x, y, len, 75 m_span_gen->generate(x, y, len), 76 solid ? 0 : covers, 77 *covers); 78 } 79 } 80 if(--num_spans == 0) { 81 break; 82 } 83 ++span; 84 } 85 } 86 } while(m_ren->next_clip_box()); 87 } 88 private: 89 base_ren_type* m_ren; 90 SpanGenerator* m_span_gen; 91 }; 92 } 93 #endif 94