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Diffstat (limited to 'src/agg/agg_rasterizer_scanline_aa_nogamma.h')
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1 files changed, 483 insertions, 0 deletions
diff --git a/src/agg/agg_rasterizer_scanline_aa_nogamma.h b/src/agg/agg_rasterizer_scanline_aa_nogamma.h new file mode 100644 index 000000000..9a809aa5a --- /dev/null +++ b/src/agg/agg_rasterizer_scanline_aa_nogamma.h @@ -0,0 +1,483 @@ +//---------------------------------------------------------------------------- +// Anti-Grain Geometry - Version 2.4 +// Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com) +// +// Permission to copy, use, modify, sell and distribute this software +// is granted provided this copyright notice appears in all copies. +// This software is provided "as is" without express or implied +// warranty, and with no claim as to its suitability for any purpose. +// +//---------------------------------------------------------------------------- +// +// The author gratefully acknowleges the support of David Turner, +// Robert Wilhelm, and Werner Lemberg - the authors of the FreeType +// libray - in producing this work. See http://www.freetype.org for details. +// +//---------------------------------------------------------------------------- +// Contact: mcseem@antigrain.com +// mcseemagg@yahoo.com +// http://www.antigrain.com +//---------------------------------------------------------------------------- +// +// Adaptation for 32-bit screen coordinates has been sponsored by +// Liberty Technology Systems, Inc., visit http://lib-sys.com +// +// Liberty Technology Systems, Inc. is the provider of +// PostScript and PDF technology for software developers. +// +//---------------------------------------------------------------------------- +#ifndef AGG_RASTERIZER_SCANLINE_AA_NOGAMMA_INCLUDED +#define AGG_RASTERIZER_SCANLINE_AA_NOGAMMA_INCLUDED + +#include <limits> +#include "agg_rasterizer_cells_aa.h" +#include "agg_rasterizer_sl_clip.h" + + +namespace agg +{ + + + //-----------------------------------------------------------------cell_aa + // A pixel cell. There're no constructors defined and it was done + // intentionally in order to avoid extra overhead when allocating an + // array of cells. + struct cell_aa + { + int x; + int y; + int cover; + int area; + + void initial() + { + x = std::numeric_limits<int>::max(); + y = std::numeric_limits<int>::max(); + cover = 0; + area = 0; + } + + void style(const cell_aa&) {} + + int not_equal(int ex, int ey, const cell_aa&) const + { + return ((unsigned)ex - (unsigned)x) | ((unsigned)ey - (unsigned)y); + } + }; + + + //==================================================rasterizer_scanline_aa_nogamma + // Polygon rasterizer that is used to render filled polygons with + // high-quality Anti-Aliasing. Internally, by default, the class uses + // integer coordinates in format 24.8, i.e. 24 bits for integer part + // and 8 bits for fractional - see poly_subpixel_shift. This class can be + // used in the following way: + // + // 1. filling_rule(filling_rule_e ft) - optional. + // + // 2. gamma() - optional. + // + // 3. reset() + // + // 4. move_to(x, y) / line_to(x, y) - make the polygon. One can create + // more than one contour, but each contour must consist of at least 3 + // vertices, i.e. move_to(x1, y1); line_to(x2, y2); line_to(x3, y3); + // is the absolute minimum of vertices that define a triangle. + // The algorithm does not check either the number of vertices nor + // coincidence of their coordinates, but in the worst case it just + // won't draw anything. + // The orger of the vertices (clockwise or counterclockwise) + // is important when using the non-zero filling rule (fill_non_zero). + // In this case the vertex order of all the contours must be the same + // if you want your intersecting polygons to be without "holes". + // You actually can use different vertices order. If the contours do not + // intersect each other the order is not important anyway. If they do, + // contours with the same vertex order will be rendered without "holes" + // while the intersecting contours with different orders will have "holes". + // + // filling_rule() and gamma() can be called anytime before "sweeping". + //------------------------------------------------------------------------ + template<class Clip=rasterizer_sl_clip_int> class rasterizer_scanline_aa_nogamma + { + enum status + { + status_initial, + status_move_to, + status_line_to, + status_closed + }; + + public: + typedef Clip clip_type; + typedef typename Clip::conv_type conv_type; + typedef typename Clip::coord_type coord_type; + + enum aa_scale_e + { + aa_shift = 8, + aa_scale = 1 << aa_shift, + aa_mask = aa_scale - 1, + aa_scale2 = aa_scale * 2, + aa_mask2 = aa_scale2 - 1 + }; + + //-------------------------------------------------------------------- + rasterizer_scanline_aa_nogamma() : + m_outline(), + m_clipper(), + m_filling_rule(fill_non_zero), + m_auto_close(true), + m_start_x(0), + m_start_y(0), + m_status(status_initial) + { + } + + //-------------------------------------------------------------------- + void reset(); + void reset_clipping(); + void clip_box(double x1, double y1, double x2, double y2); + void filling_rule(filling_rule_e filling_rule); + void auto_close(bool flag) { m_auto_close = flag; } + + //-------------------------------------------------------------------- + unsigned apply_gamma(unsigned cover) const + { + return cover; + } + + //-------------------------------------------------------------------- + void move_to(int x, int y); + void line_to(int x, int y); + void move_to_d(double x, double y); + void line_to_d(double x, double y); + void close_polygon(); + void add_vertex(double x, double y, unsigned cmd); + + void edge(int x1, int y1, int x2, int y2); + void edge_d(double x1, double y1, double x2, double y2); + + //------------------------------------------------------------------- + template<class VertexSource> + void add_path(VertexSource& vs, unsigned path_id=0) + { + double x; + double y; + + unsigned cmd; + vs.rewind(path_id); + if(m_outline.sorted()) reset(); + while(!is_stop(cmd = vs.vertex(&x, &y))) + { + add_vertex(x, y, cmd); + } + } + + //-------------------------------------------------------------------- + int min_x() const { return m_outline.min_x(); } + int min_y() const { return m_outline.min_y(); } + int max_x() const { return m_outline.max_x(); } + int max_y() const { return m_outline.max_y(); } + + //-------------------------------------------------------------------- + void sort(); + bool rewind_scanlines(); + bool navigate_scanline(int y); + + //-------------------------------------------------------------------- + AGG_INLINE unsigned calculate_alpha(int area) const + { + int cover = area >> (poly_subpixel_shift*2 + 1 - aa_shift); + + if(cover < 0) cover = -cover; + if(m_filling_rule == fill_even_odd) + { + cover &= aa_mask2; + if(cover > aa_scale) + { + cover = aa_scale2 - cover; + } + } + if(cover > aa_mask) cover = aa_mask; + return cover; + } + + //-------------------------------------------------------------------- + template<class Scanline> bool sweep_scanline(Scanline& sl) + { + for(;;) + { + if(m_scan_y > m_outline.max_y()) return false; + sl.reset_spans(); + unsigned num_cells = m_outline.scanline_num_cells(m_scan_y); + const cell_aa* const* cells = m_outline.scanline_cells(m_scan_y); + int cover = 0; + + while(num_cells) + { + const cell_aa* cur_cell = *cells; + int x = cur_cell->x; + int area = cur_cell->area; + unsigned alpha; + + cover += cur_cell->cover; + + //accumulate all cells with the same X + while(--num_cells) + { + cur_cell = *++cells; + if(cur_cell->x != x) break; + area += cur_cell->area; + cover += cur_cell->cover; + } + + if(area) + { + alpha = calculate_alpha((cover << (poly_subpixel_shift + 1)) - area); + if(alpha) + { + sl.add_cell(x, alpha); + } + x++; + } + + if(num_cells && cur_cell->x > x) + { + alpha = calculate_alpha(cover << (poly_subpixel_shift + 1)); + if(alpha) + { + sl.add_span(x, cur_cell->x - x, alpha); + } + } + } + + if(sl.num_spans()) break; + ++m_scan_y; + } + + sl.finalize(m_scan_y); + ++m_scan_y; + return true; + } + + //-------------------------------------------------------------------- + bool hit_test(int tx, int ty); + + + private: + //-------------------------------------------------------------------- + // Disable copying + rasterizer_scanline_aa_nogamma(const rasterizer_scanline_aa_nogamma<Clip>&); + const rasterizer_scanline_aa_nogamma<Clip>& + operator = (const rasterizer_scanline_aa_nogamma<Clip>&); + + private: + rasterizer_cells_aa<cell_aa> m_outline; + clip_type m_clipper; + filling_rule_e m_filling_rule; + bool m_auto_close; + coord_type m_start_x; + coord_type m_start_y; + unsigned m_status; + int m_scan_y; + }; + + + + + + + + + + + + + //------------------------------------------------------------------------ + template<class Clip> + void rasterizer_scanline_aa_nogamma<Clip>::reset() + { + m_outline.reset(); + m_status = status_initial; + } + + //------------------------------------------------------------------------ + template<class Clip> + void rasterizer_scanline_aa_nogamma<Clip>::filling_rule(filling_rule_e filling_rule) + { + m_filling_rule = filling_rule; + } + + //------------------------------------------------------------------------ + template<class Clip> + void rasterizer_scanline_aa_nogamma<Clip>::clip_box(double x1, double y1, + double x2, double y2) + { + reset(); + m_clipper.clip_box(conv_type::upscale(x1), conv_type::upscale(y1), + conv_type::upscale(x2), conv_type::upscale(y2)); + } + + //------------------------------------------------------------------------ + template<class Clip> + void rasterizer_scanline_aa_nogamma<Clip>::reset_clipping() + { + reset(); + m_clipper.reset_clipping(); + } + + //------------------------------------------------------------------------ + template<class Clip> + void rasterizer_scanline_aa_nogamma<Clip>::close_polygon() + { + if(m_status == status_line_to) + { + m_clipper.line_to(m_outline, m_start_x, m_start_y); + m_status = status_closed; + } + } + + //------------------------------------------------------------------------ + template<class Clip> + void rasterizer_scanline_aa_nogamma<Clip>::move_to(int x, int y) + { + if(m_outline.sorted()) reset(); + if(m_auto_close) close_polygon(); + m_clipper.move_to(m_start_x = conv_type::downscale(x), + m_start_y = conv_type::downscale(y)); + m_status = status_move_to; + } + + //------------------------------------------------------------------------ + template<class Clip> + void rasterizer_scanline_aa_nogamma<Clip>::line_to(int x, int y) + { + m_clipper.line_to(m_outline, + conv_type::downscale(x), + conv_type::downscale(y)); + m_status = status_line_to; + } + + //------------------------------------------------------------------------ + template<class Clip> + void rasterizer_scanline_aa_nogamma<Clip>::move_to_d(double x, double y) + { + if(m_outline.sorted()) reset(); + if(m_auto_close) close_polygon(); + m_clipper.move_to(m_start_x = conv_type::upscale(x), + m_start_y = conv_type::upscale(y)); + m_status = status_move_to; + } + + //------------------------------------------------------------------------ + template<class Clip> + void rasterizer_scanline_aa_nogamma<Clip>::line_to_d(double x, double y) + { + m_clipper.line_to(m_outline, + conv_type::upscale(x), + conv_type::upscale(y)); + m_status = status_line_to; + } + + //------------------------------------------------------------------------ + template<class Clip> + void rasterizer_scanline_aa_nogamma<Clip>::add_vertex(double x, double y, unsigned cmd) + { + if(is_move_to(cmd)) + { + move_to_d(x, y); + } + else + if(is_vertex(cmd)) + { + line_to_d(x, y); + } + else + if(is_close(cmd)) + { + close_polygon(); + } + } + + //------------------------------------------------------------------------ + template<class Clip> + void rasterizer_scanline_aa_nogamma<Clip>::edge(int x1, int y1, int x2, int y2) + { + if(m_outline.sorted()) reset(); + m_clipper.move_to(conv_type::downscale(x1), conv_type::downscale(y1)); + m_clipper.line_to(m_outline, + conv_type::downscale(x2), + conv_type::downscale(y2)); + m_status = status_move_to; + } + + //------------------------------------------------------------------------ + template<class Clip> + void rasterizer_scanline_aa_nogamma<Clip>::edge_d(double x1, double y1, + double x2, double y2) + { + if(m_outline.sorted()) reset(); + m_clipper.move_to(conv_type::upscale(x1), conv_type::upscale(y1)); + m_clipper.line_to(m_outline, + conv_type::upscale(x2), + conv_type::upscale(y2)); + m_status = status_move_to; + } + + //------------------------------------------------------------------------ + template<class Clip> + void rasterizer_scanline_aa_nogamma<Clip>::sort() + { + if(m_auto_close) close_polygon(); + m_outline.sort_cells(); + } + + //------------------------------------------------------------------------ + template<class Clip> + AGG_INLINE bool rasterizer_scanline_aa_nogamma<Clip>::rewind_scanlines() + { + if(m_auto_close) close_polygon(); + m_outline.sort_cells(); + if(m_outline.total_cells() == 0) + { + return false; + } + m_scan_y = m_outline.min_y(); + return true; + } + + + //------------------------------------------------------------------------ + template<class Clip> + AGG_INLINE bool rasterizer_scanline_aa_nogamma<Clip>::navigate_scanline(int y) + { + if(m_auto_close) close_polygon(); + m_outline.sort_cells(); + if(m_outline.total_cells() == 0 || + y < m_outline.min_y() || + y > m_outline.max_y()) + { + return false; + } + m_scan_y = y; + return true; + } + + //------------------------------------------------------------------------ + template<class Clip> + bool rasterizer_scanline_aa_nogamma<Clip>::hit_test(int tx, int ty) + { + if(!navigate_scanline(ty)) return false; + scanline_hit_test sl(tx); + sweep_scanline(sl); + return sl.hit(); + } + + + +} + + + +#endif + |