| |
| //---------------------------------------------------------------------------- |
| // XYQ: 2006-01-22 Copied from AGG project. |
| // TODO: This file uses intensive floating point operations, so it's NOT suitable |
| // for platforms like Symbian OS. We need to change to FIX format. |
| //---------------------------------------------------------------------------- |
| //---------------------------------------------------------------------------- |
| // Anti-Grain Geometry - Version 2.3 |
| // 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. |
| // |
| //---------------------------------------------------------------------------- |
| // Contact: mcseem@antigrain.com |
| // mcseemagg@yahoo.com |
| // http://www.antigrain.com |
| //---------------------------------------------------------------------------- |
| |
| #include "agg_curves.h" |
| #include "agg_math.h" |
| |
| namespace agg |
| { |
| const float curve_collinearity_epsilon = 1e-30f; |
| enum curve_recursion_limit_e { curve_recursion_limit = 16 }; |
| void curve4_div::init(float x1, float y1, |
| float x2, float y2, |
| float x3, float y3, |
| float x4, float y4) |
| { |
| m_points.remove_all(); |
| m_distance_tolerance_square = 1.0f / 4; |
| m_distance_tolerance_manhattan = 1.0f * 4; |
| bezier(x1, y1, x2, y2, x3, y3, x4, y4); |
| m_count = 0; |
| } |
| void curve4_div::recursive_bezier(float x1, float y1, |
| float x2, float y2, |
| float x3, float y3, |
| float x4, float y4, |
| unsigned level) |
| { |
| if(level > curve_recursion_limit) { |
| return; |
| } |
| float x12 = (x1 + x2) / 2; |
| float y12 = (y1 + y2) / 2; |
| float x23 = (x2 + x3) / 2; |
| float y23 = (y2 + y3) / 2; |
| float x34 = (x3 + x4) / 2; |
| float y34 = (y3 + y4) / 2; |
| float x123 = (x12 + x23) / 2; |
| float y123 = (y12 + y23) / 2; |
| float x234 = (x23 + x34) / 2; |
| float y234 = (y23 + y34) / 2; |
| float x1234 = (x123 + x234) / 2; |
| float y1234 = (y123 + y234) / 2; |
| float dx = x4 - x1; |
| float dy = y4 - y1; |
| float d2 = fabs(((x2 - x4) * dy) - ((y2 - y4) * dx)); |
| float d3 = fabs(((x3 - x4) * dy) - ((y3 - y4) * dx)); |
| switch((int(d2 > curve_collinearity_epsilon) << 1) + |
| int(d3 > curve_collinearity_epsilon)) { |
| case 0: |
| if (fabs(x1 + x3 - x2 - x2) + fabs(y1 + y3 - y2 - y2) + |
| fabs(x2 + x4 - x3 - x3) + fabs(y2 + y4 - y3 - y3) <= |
| m_distance_tolerance_manhattan) { |
| m_points.add(point_type(x1234, y1234, path_flags_jr)); |
| return; |
| } |
| break; |
| case 1: |
| if ((d3 * d3) <= |
| (m_distance_tolerance_square * ((dx * dx) + (dy * dy)))) { |
| m_points.add(point_type(x23, y23, path_flags_jr)); |
| return; |
| } |
| break; |
| case 2: |
| if ((d2 * d2) <= |
| (m_distance_tolerance_square * ((dx * dx) + (dy * dy)))) { |
| m_points.add(point_type(x23, y23, path_flags_jr)); |
| return; |
| } |
| break; |
| case 3: |
| if (((d2 + d3) * (d2 + d3)) <= |
| (m_distance_tolerance_square * ((dx * dx) + (dy * dy)))) { |
| m_points.add(point_type(x23, y23, path_flags_jr)); |
| return; |
| } |
| break; |
| } |
| recursive_bezier(x1, y1, x12, y12, x123, y123, x1234, y1234, level + 1); |
| recursive_bezier(x1234, y1234, x234, y234, x34, y34, x4, y4, level + 1); |
| } |
| void curve4_div::bezier(float x1, float y1, |
| float x2, float y2, |
| float x3, float y3, |
| float x4, float y4) |
| { |
| m_points.add(point_type(x1, y1)); |
| recursive_bezier(x1, y1, x2, y2, x3, y3, x4, y4, 0); |
| m_points.add(point_type(x4, y4)); |
| } |
| } |