4 // Various graphic functions that are slightly more complex than those that
5 // come with various widget libraries.
8 // (C) 2005 Underground Software
10 // JLH = James L. Hammons <jlhamm@acm.org>
13 // --- ---------- -------------------------------------------------------------
14 // JLH 03/14/1998 Created this file
15 // JLH 01/20/2005 Converted to use wxWidgets
16 // JLH 08/30/2008 Repurposed file to handle more than just bezier curves
19 #include "graphicprimitives.h"
21 double abs(double n) // Helper function
23 return (n < 0 ? -n : n);
28 // This function takes three points and draws a curve using a second order
31 void Bezier(QPainter &p, point p1, point p2, point p3)
33 double step = abs(p1.x - p3.x), tmp = abs(p1.y - p3.y);
34 step = (tmp > step ? tmp : step); // Get the larger of the two...
35 step = (step > 0 ? 1/step : 1); // & convert to valid step value
36 step *= 2.0; // (double it to draw less...)
38 int prevX = (int)p1.x, prevY = (int)p1.y;
40 for(double u=0; u<=1; u+=step)
42 double _2u = 2*u, _uu = u*u, _2uu = 2*_uu;
43 double x = (p1.x * (1 - _2u + _uu)) + (p2.x * (_2u - _2uu)) + (p3.x * _uu);
44 double y = (p1.y * (1 - _2u + _uu)) + (p2.y * (_2u - _2uu)) + (p3.y * _uu);
46 p.drawLine(prevX, prevY, (int)x, (int)y);
47 prevX = (int)x, prevY = (int)y;
50 p.drawLine(prevX, prevY, (int)p3.x, (int)p3.y);
55 // This is a convenience funtion, using IPoints :-)
57 void Bezier(QPainter &p, IPoint p1, IPoint p2, IPoint p3)
59 Bezier(p, point(p1.x, p1.y), point(p2.x, p2.y), point(p3.x, p3.y));
64 // Draw a round dot (5x5, centered on [x, y])
66 void DrawRoundDot(QPainter &p, int32_t x, int32_t y)
70 pt[0] = QPoint(x - 1, y - 2);
71 pt[1] = QPoint(x + 1, y - 2);
72 pt[2] = QPoint(x + 2, y - 1);
73 pt[3] = QPoint(x + 2, y + 1);
74 pt[4] = QPoint(x + 1, y + 2);
75 pt[5] = QPoint(x - 1, y + 2);
76 pt[6] = QPoint(x - 2, y + 1);
77 pt[7] = QPoint(x - 2, y - 1);
84 // Draw a sqaure dot (5x5, centered on [x, y])
86 void DrawSquareDot(QPainter &p, int32_t x, int32_t y)
90 pt[0] = QPoint(x - 2, y - 2);
91 pt[1] = QPoint(x + 2, y - 2);
92 pt[2] = QPoint(x + 2, y + 2);
93 pt[3] = QPoint(x - 2, y + 2);
100 // Draw a sqaure dot (nxn, centered on [x, y])
102 void DrawSquareDotN(QPainter &p, int32_t x, int32_t y, uint32_t n)
105 uint32_t offset = (n - 1) / 2;
107 pt[0] = QPoint(x - offset, y - offset);
108 pt[1] = QPoint(x + offset, y - offset);
109 pt[2] = QPoint(x + offset, y + offset);
110 pt[3] = QPoint(x - offset, y + offset);
112 p.drawPolygon(pt, 4);
117 // Draw a round dot (nxn, centered on [x, y])
119 void DrawRoundDotN(QPainter &p, int32_t x, int32_t y, uint32_t n)
121 int radius = (n / 2) + 1;
122 p.drawEllipse(x - radius, y - radius, n, n);