mirrors/fltk
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

copied more documentation from drawing.dox to {fl_curve,fl_vertex}.cxx

Browse Source 
git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3@6430 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
This commit is contained in:
engelsman 2008-10-14 21:42:24 +00:00
parent 7a90386c6d
commit e08fffdfe0
3 changed files with 129 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
FL/fl_draw.H
View File

@ -115,6 +115,7 @@ FL_EXPORT void fl_yxline(int x, int y, int y1, int x2, int y3);
// circular lines and pie slices (code in fl_arci.C):
FL_EXPORT void fl_arc(int x, int y, int w, int h, double a1, double a2);
FL_EXPORT void fl_pie(int x, int y, int w, int h, double a1, double a2);
/** fl_chord declaration is a place holder - the function does not yet exist */
FL_EXPORT void fl_chord(int x, int y, int w, int h, double a1, double a2); // nyi
// scalable drawing code (code in fl_vertex.C and fl_arc.C):
@ -130,7 +131,7 @@ FL_EXPORT void fl_begin_line();
FL_EXPORT void fl_begin_loop();
FL_EXPORT void fl_begin_polygon();
FL_EXPORT void fl_vertex(double x, double y);
FL_EXPORT void fl_curve(double, double, double, double, double, double, double, double);
FL_EXPORT void fl_curve(double X0, double Y0, double X1, double Y1, double X2, double Y2, double X3, double Y3);
FL_EXPORT void fl_arc(double x, double y, double r, double start, double a);
FL_EXPORT void fl_circle(double x, double y, double r);
FL_EXPORT void fl_end_points();

18
src/fl_curve.cxx
View File

@ -25,6 +25,16 @@
// http://www.fltk.org/str.php
//
/**
\file fl_curve.cxx
\brief Utility for drawing Bezier curves, adding the points to the
current fl_begin/fl_vertex/fl_end path.
Incremental math implementation:
I very much doubt this is optimal! From Foley/vanDam page 511.
If anybody has a better algorithim, please send it!
*/
// Utility for drawing Bezier curves, adding the points to
// the current fl_begin/fl_vertex/fl_end path.
// Incremental math implementation:
@ -34,6 +44,14 @@
#include <FL/fl_draw.H>
#include <math.h>
/**
Add a series of points on a Bezier curve to the path.
The curve ends (and two of the points) are at X0,Y0 and X3,Y3.
\param[in] X0,Y0 curve start point
\param[in] X1,Y1 curve control point
\param[in] X2,Y2 curve control point
\param[in] X3,Y3 curve end point
*/
void fl_curve(double X0, double Y0,
double X1, double Y1,
double X2, double Y2,

109
src/fl_vertex.cxx
View File

@ -25,6 +25,12 @@
// http://www.fltk.org/str.php
//
/**
\file fl_vertex.cxx
\brief Portable drawing code for drawing arbitrary shapes with
simple 2D transformations.
*/
// Portable drawing code for drawing arbitrary shapes with
// simple 2D transformations. See also fl_arc.cxx
@ -45,6 +51,10 @@ static matrix m = {1, 0, 0, 1, 0, 0};
static matrix stack[32];
static int sptr = 0;
/**
Save the current transformation matrix on the stack.
The maximum depth of the stack is 4.
*/
void fl_push_matrix() {
if (sptr==32)
Fl::error("fl_push_matrix(): matrix stack overflow.");
@ -52,6 +62,9 @@ void fl_push_matrix() {
stack[sptr++] = m;
}
/**
Restore the current transformation matrix from the stack.
*/
void fl_pop_matrix() {
if (sptr==0)
Fl::error("fl_pop_matrix(): matrix stack underflow.");
@ -59,6 +72,11 @@ void fl_pop_matrix() {
m = stack[--sptr];
}
/**
Concatenate another transformation onto the current one.
\param[in] a,b,c,d,x,y transformation matrix elements such that
<tt> X' = aX + cY + x </tt> and <tt> Y' = bX +dY + y </tt>
*/
void fl_mult_matrix(double a, double b, double c, double d, double x, double y) {
matrix o;
o.a = a*m.a + b*m.c;
@ -70,12 +88,28 @@ void fl_mult_matrix(double a, double b, double c, double d, double x, double y)
m = o;
}
/**
Concatenate scaling transformation onto the current one.
\param[in] x,y scale factors in x-direction and y-direction
*/
void fl_scale(double x,double y) {fl_mult_matrix(x,0,0,y,0,0);}
/**
Concatenate scaling transformation onto the current one.
\param[in] x scale factor in both x-direction and y-direction
*/
void fl_scale(double x) {fl_mult_matrix(x,0,0,x,0,0);}
/**
Concatenate translation transformation onto the current one.
\param[in] x,y translation factor in x-direction and y-direction
*/
void fl_translate(double x,double y) {fl_mult_matrix(1,0,0,1,x,y);}
/**
Concatenate rotation transformation onto the current one.
\param[in] d - rotation angle, counter-clockwise in degrees (not radians)
*/
void fl_rotate(double d) {
if (d) {
double s, c;
@ -109,20 +143,48 @@ static int n;
static int what;
enum {LINE, LOOP, POLYGON, POINT_};
/**
Start drawing a list of points. Points are added to the list with fl_vertex()
*/
void fl_begin_points() {n = 0; what = POINT_;}
/**
Start drawing a list of lines.
*/
void fl_begin_line() {n = 0; what = LINE;}
/**
Start drawing a closed sequence of lines.
*/
void fl_begin_loop() {n = 0; what = LOOP;}
/**
Start drawing a convex filled polygon.
*/
void fl_begin_polygon() {n = 0; what = POLYGON;}
/**
Transform coordinate using current transformation matrix.
\param[in] x,y coordinate
*/
double fl_transform_x(double x, double y) {return x*m.a + y*m.c + m.x;}
/**
Transform coordinate using current transformation matrix.
\param[in] x,y coordinate
*/
double fl_transform_y(double x, double y) {return x*m.b + y*m.d + m.y;}
/**
Transform distance using current transformation matrix.
\param[in] x,y coordinate
*/
double fl_transform_dx(double x, double y) {return x*m.a + y*m.c;}
/**
Transform distance using current transformation matrix.
\param[in] x,y coordinate
*/
double fl_transform_dy(double x, double y) {return x*m.b + y*m.d;}
static void fl_transformed_vertex(COORD_T x, COORD_T y) {
@ -137,6 +199,10 @@ static void fl_transformed_vertex(COORD_T x, COORD_T y) {
}
}
/**
Add coordinate pair to the vertex list without further transformations.
\param[in] xf,yf transformed coordinate
*/
void fl_transformed_vertex(double xf, double yf) {
#ifdef __APPLE_QUARTZ__
fl_transformed_vertex(COORD_T(xf), COORD_T(yf));
@ -145,10 +211,17 @@ void fl_transformed_vertex(double xf, double yf) {
#endif
}
/**
Add a single vertex to the current path.
\param[in] x,y coordinate
*/
void fl_vertex(double x,double y) {
fl_transformed_vertex(x*m.a + y*m.c + m.x, x*m.b + y*m.d + m.y);
}
/**
End list of points, and draw
*/
void fl_end_points() {
#if defined(USE_X11)
if (n>1) XDrawPoints(fl_display, fl_window, fl_gc, p, n, 0);
@ -167,6 +240,9 @@ void fl_end_points() {
#endif
}
/**
End list of lines, and draw
*/
void fl_end_line() {
if (n < 2) {
fl_end_points();
@ -191,12 +267,18 @@ static void fixloop() { // remove equal points from closed path
while (n>2 && p[n-1].x == p[0].x && p[n-1].y == p[0].y) n--;
}
/**
End closed sequence of lines, and draw
*/
void fl_end_loop() {
fixloop();
if (n>2) fl_transformed_vertex((COORD_T)p[0].x, (COORD_T)p[0].y);
fl_end_line();
}
/**
End convex filled polygon, and draw
*/
void fl_end_polygon() {
fixloop();
if (n < 3) {
@ -228,6 +310,19 @@ static int counts[20];
static int numcount;
#endif
/**
Start drawing a complex filled polygon. The polygon may be concave, may
have holes in it, or may be several disconnected pieces. Call fl_gap() to
seperate loops of the path.
To outline the polygone, use fl_begin_loop() and reaplace each fl_gap()
with fl_end_loop();fl_begin_loop() pairs.
\note
For portability, you should only draw polygons that appear the same
whether "even/odd" or "non-zero" winding rules are used to fill them.
Holes should be drawn in the opposite direction to the outside loop.
*/
void fl_begin_complex_polygon() {
fl_begin_polygon();
gap = 0;
@ -236,6 +331,11 @@ void fl_begin_complex_polygon() {
#endif
}
/**
Call fl_gap() to separate loops of the path.
It is unnecessary but harmless to call fl_gap() before the first vertex,
after the last vertex, or several times in a row.
*/
void fl_gap() {
while (n>gap+2 && p[n-1].x == p[gap].x && p[n-1].y == p[gap].y) n--;
if (n > gap+2) {
@ -249,6 +349,9 @@ void fl_gap() {
}
}
/**
End complex filled polygon, and draw
*/
void fl_end_complex_polygon() {
fl_gap();
if (n < 3) {
@ -278,6 +381,12 @@ void fl_end_complex_polygon() {
// warning: these do not draw rotated ellipses correctly!
// See fl_arc.c for portable version.
/**
fl_circle() is equivalent to fl_arc(...,0,360) but may be faster.
It must be the \e only thing in the path: if you want a circle as part of
a complex polygon you must use fl_arc()
\param[in] x,y,r center and radius of circle
*/
void fl_circle(double x, double y,double r) {
double xt = fl_transform_x(x,y);
double yt = fl_transform_y(x,y);