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diff --git a/src/drivers/Xlib/Fl_Xlib_Graphics_Driver_rect.cxx b/src/drivers/Xlib/Fl_Xlib_Graphics_Driver_rect.cxx
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+//
+// "$Id$"
+//
+// Rectangle drawing routines for the Fast Light Tool Kit (FLTK).
+//
+// Copyright 1998-2012 by Bill Spitzak and others.
+//
+// This library is free software. Distribution and use rights are outlined in
+// the file "COPYING" which should have been included with this file. If this
+// file is missing or damaged, see the license at:
+//
+// http://www.fltk.org/COPYING.php
+//
+// Please report all bugs and problems on the following page:
+//
+// http://www.fltk.org/str.php
+//
+
+
+#ifndef FL_CFG_GFX_XLIB_RECT_CXX
+#define FL_CFG_GFX_XLIB_RECT_CXX
+
+
+/**
+ \file xlib_rect.cxx
+ \brief X11 Xlib specific line and polygon drawing with integer coordinates.
+ */
+
+
+#include "Fl_Xlib_Graphics_Driver.h"
+
+
+#ifndef SHRT_MAX
+#define SHRT_MAX (32767)
+#endif
+
+/*
+ We need to check some coordinates for areas for clipping before we
+ use X functions, because X can't handle coordinates outside the 16-bit
+ range. Since all windows use relative coordinates > 0, we do also
+ check for negative values. X11 only, see also STR #2304.
+
+ Note that this is only necessary for large objects, where only a
+ part of the object is visible. The draw() functions (e.g. box
+ drawing) must be clipped correctly. This is usually only a matter
+ for large container widgets. The individual child widgets will be
+ clipped completely.
+
+ We define the usable X coordinate space as [ -LW : SHRT_MAX - LW ]
+ where LW = current line width for drawing. This is done so that
+ horizontal and vertical line drawing works correctly, even in real
+ border cases, e.g. drawing a rectangle slightly outside the top left
+ window corner, but with a line width so that a part of the line should
+ be visible (in this case 2 of 5 pixels):
+
+ fl_line_style (FL_SOLID,5); // line width = 5
+ fl_rect (-1,-1,100,100); // top/left: 2 pixels visible
+
+ In this example case, no clipping would be done, because X can
+ handle it and clip unneeded pixels.
+
+ Note that we must also take care of the case where fl_line_width_
+ is zero (maybe unitialized). If this is the case, we assume a line
+ width of 1.
+
+ Todo: Arbitrary line drawings (e.g. polygons) and clip regions
+ are not yet done.
+
+ Note:
+
+ We could use max. screen coordinates instead of SHRT_MAX, but that
+ would need more work and would probably be slower. We assume that
+ all window coordinates are >= 0 and that no window extends up to
+ 32767 - LW (where LW = current line width). Thus it is safe to clip
+ all coordinates to this range before calling X functions. If this
+ is not true, then clip_to_short() and clip_x() must be redefined.
+
+ It would be somewhat easier if we had fl_clip_w and fl_clip_h, as
+ defined in FLTK 2.0 (for the upper clipping bounds)...
+ */
+
+/*
+ clip_to_short() returns 1, if the area is invisible (clipped),
+ because ...
+
+ (a) w or h are <= 0 i.e. nothing is visible
+ (b) x+w or y+h are < kmin i.e. left of or above visible area
+ (c) x or y are > kmax i.e. right of or below visible area
+
+ kmin and kmax are the minimal and maximal X coordinate values,
+ as defined above. In this case x, y, w, and h are not changed.
+
+ It returns 0, if the area is potentially visible and X can handle
+ clipping. x, y, w, and h may have been adjusted to fit into the
+ X coordinate space.
+
+ Use this for clipping rectangles, as used in fl_rect() and
+ fl_rectf().
+ */
+static int clip_to_short(int &x, int &y, int &w, int &h) {
+
+ int lw = (fl_line_width_ > 0) ? fl_line_width_ : 1;
+ int kmin = -lw;
+ int kmax = SHRT_MAX - lw;
+
+ if (w <= 0 || h <= 0) return 1; // (a)
+ if (x+w < kmin || y+h < kmin) return 1; // (b)
+ if (x > kmax || y > kmax) return 1; // (c)
+
+ if (x < kmin) { w -= (kmin-x); x = kmin; }
+ if (y < kmin) { h -= (kmin-y); y = kmin; }
+ if (x+w > kmax) w = kmax - x;
+ if (y+h > kmax) h = kmax - y;
+
+ return 0;
+}
+
+/*
+ clip_x() returns a coordinate value clipped to the 16-bit coordinate
+ space (see above). This can be used to draw horizontal and vertical
+ lines that can be handled by X11. Each single coordinate value can
+ be clipped individually, and the result can be used directly, e.g.
+ in fl_xyline() and fl_yxline(). Note that this can't be used for
+ arbitrary lines (not horizontal or vertical).
+ */
+static int clip_x (int x) {
+
+ int lw = (fl_line_width_ > 0) ? fl_line_width_ : 1;
+ int kmin = -lw;
+ int kmax = SHRT_MAX - lw;
+
+ if (x < kmin)
+ x = kmin;
+ else if (x > kmax)
+ x = kmax;
+ return x;
+}
+
+// Missing X call: (is this the fastest way to init a 1-rectangle region?)
+// MSWindows equivalent exists, implemented inline in win32.H
+Fl_Region XRectangleRegion(int x, int y, int w, int h) {
+ XRectangle R;
+ clip_to_short(x, y, w, h);
+ R.x = x; R.y = y; R.width = w; R.height = h;
+ Fl_Region r = XCreateRegion();
+ XUnionRectWithRegion(&R, r, r);
+ return r;
+}
+
+// --- line and polygon drawing with integer coordinates
+
+void Fl_Xlib_Graphics_Driver::point(int x, int y) {
+ XDrawPoint(fl_display, fl_window, fl_gc, clip_x(x), clip_x(y));
+}
+
+void Fl_Xlib_Graphics_Driver::rect(int x, int y, int w, int h) {
+ if (w<=0 || h<=0) return;
+ if (!clip_to_short(x, y, w, h))
+ XDrawRectangle(fl_display, fl_window, fl_gc, x, y, w-1, h-1);
+}
+
+void Fl_Xlib_Graphics_Driver::rectf(int x, int y, int w, int h) {
+ if (w<=0 || h<=0) return;
+ if (!clip_to_short(x, y, w, h))
+ XFillRectangle(fl_display, fl_window, fl_gc, x, y, w, h);
+}
+
+void Fl_Xlib_Graphics_Driver::line(int x, int y, int x1, int y1) {
+ XDrawLine(fl_display, fl_window, fl_gc, x, y, x1, y1);
+}
+
+void Fl_Xlib_Graphics_Driver::line(int x, int y, int x1, int y1, int x2, int y2) {
+ XPoint p[3];
+ p[0].x = x; p[0].y = y;
+ p[1].x = x1; p[1].y = y1;
+ p[2].x = x2; p[2].y = y2;
+ XDrawLines(fl_display, fl_window, fl_gc, p, 3, 0);
+}
+
+void Fl_Xlib_Graphics_Driver::xyline(int x, int y, int x1) {
+ XDrawLine(fl_display, fl_window, fl_gc, clip_x(x), clip_x(y), clip_x(x1), clip_x(y));
+}
+
+void Fl_Xlib_Graphics_Driver::xyline(int x, int y, int x1, int y2) {
+ XPoint p[3];
+ p[0].x = clip_x(x); p[0].y = p[1].y = clip_x(y);
+ p[1].x = p[2].x = clip_x(x1); p[2].y = clip_x(y2);
+ XDrawLines(fl_display, fl_window, fl_gc, p, 3, 0);
+}
+
+void Fl_Xlib_Graphics_Driver::xyline(int x, int y, int x1, int y2, int x3) {
+ XPoint p[4];
+ p[0].x = clip_x(x); p[0].y = p[1].y = clip_x(y);
+ p[1].x = p[2].x = clip_x(x1); p[2].y = p[3].y = clip_x(y2);
+ p[3].x = clip_x(x3);
+ XDrawLines(fl_display, fl_window, fl_gc, p, 4, 0);
+}
+
+void Fl_Xlib_Graphics_Driver::yxline(int x, int y, int y1) {
+ XDrawLine(fl_display, fl_window, fl_gc, clip_x(x), clip_x(y), clip_x(x), clip_x(y1));
+}
+
+void Fl_Xlib_Graphics_Driver::yxline(int x, int y, int y1, int x2) {
+ XPoint p[3];
+ p[0].x = p[1].x = clip_x(x); p[0].y = clip_x(y);
+ p[1].y = p[2].y = clip_x(y1); p[2].x = clip_x(x2);
+ XDrawLines(fl_display, fl_window, fl_gc, p, 3, 0);
+}
+
+void Fl_Xlib_Graphics_Driver::yxline(int x, int y, int y1, int x2, int y3) {
+ XPoint p[4];
+ p[0].x = p[1].x = clip_x(x); p[0].y = clip_x(y);
+ p[1].y = p[2].y = clip_x(y1); p[2].x = p[3].x = clip_x(x2);
+ p[3].y = clip_x(y3);
+ XDrawLines(fl_display, fl_window, fl_gc, p, 4, 0);
+}
+
+void Fl_Xlib_Graphics_Driver::loop(int x, int y, int x1, int y1, int x2, int y2) {
+ XPoint p[4];
+ p[0].x = x; p[0].y = y;
+ p[1].x = x1; p[1].y = y1;
+ p[2].x = x2; p[2].y = y2;
+ p[3].x = x; p[3].y = y;
+ XDrawLines(fl_display, fl_window, fl_gc, p, 4, 0);
+}
+
+void Fl_Xlib_Graphics_Driver::loop(int x, int y, int x1, int y1, int x2, int y2, int x3, int y3) {
+ XPoint p[5];
+ p[0].x = x; p[0].y = y;
+ p[1].x = x1; p[1].y = y1;
+ p[2].x = x2; p[2].y = y2;
+ p[3].x = x3; p[3].y = y3;
+ p[4].x = x; p[4].y = y;
+ XDrawLines(fl_display, fl_window, fl_gc, p, 5, 0);
+}
+
+void Fl_Xlib_Graphics_Driver::polygon(int x, int y, int x1, int y1, int x2, int y2) {
+ XPoint p[4];
+ p[0].x = x; p[0].y = y;
+ p[1].x = x1; p[1].y = y1;
+ p[2].x = x2; p[2].y = y2;
+ p[3].x = x; p[3].y = y;
+ XFillPolygon(fl_display, fl_window, fl_gc, p, 3, Convex, 0);
+ XDrawLines(fl_display, fl_window, fl_gc, p, 4, 0);
+}
+
+void Fl_Xlib_Graphics_Driver::polygon(int x, int y, int x1, int y1, int x2, int y2, int x3, int y3) {
+ XPoint p[5];
+ p[0].x = x; p[0].y = y;
+ p[1].x = x1; p[1].y = y1;
+ p[2].x = x2; p[2].y = y2;
+ p[3].x = x3; p[3].y = y3;
+ p[4].x = x; p[4].y = y;
+ XFillPolygon(fl_display, fl_window, fl_gc, p, 4, Convex, 0);
+ XDrawLines(fl_display, fl_window, fl_gc, p, 5, 0);
+}
+
+// --- clipping
+
+void Fl_Xlib_Graphics_Driver::push_clip(int x, int y, int w, int h) {
+ Fl_Region r;
+ if (w > 0 && h > 0) {
+ r = XRectangleRegion(x,y,w,h);
+ Fl_Region current = rstack[rstackptr];
+ if (current) {
+ Fl_Region temp = XCreateRegion();
+ XIntersectRegion(current, r, temp);
+ XDestroyRegion(r);
+ r = temp;
+ }
+ } else { // make empty clip region:
+ r = XCreateRegion();
+ }
+ if (rstackptr < region_stack_max) rstack[++rstackptr] = r;
+ else Fl::warning("Fl_Xlib_Graphics_Driver::push_clip: clip stack overflow!\n");
+ fl_restore_clip();
+}
+
+int Fl_Xlib_Graphics_Driver::clip_box(int x, int y, int w, int h, int& X, int& Y, int& W, int& H){
+ X = x; Y = y; W = w; H = h;
+ Fl_Region r = rstack[rstackptr];
+ if (!r) return 0;
+ switch (XRectInRegion(r, x, y, w, h)) {
+ case 0: // completely outside
+ W = H = 0;
+ return 2;
+ case 1: // completely inside:
+ return 0;
+ default: // partial:
+ break;
+ }
+ Fl_Region rr = XRectangleRegion(x,y,w,h);
+ Fl_Region temp = XCreateRegion();
+ XIntersectRegion(r, rr, temp);
+ XRectangle rect;
+ XClipBox(temp, &rect);
+ X = rect.x; Y = rect.y; W = rect.width; H = rect.height;
+ XDestroyRegion(temp);
+ XDestroyRegion(rr);
+ return 1;
+}
+
+int Fl_Xlib_Graphics_Driver::not_clipped(int x, int y, int w, int h) {
+ if (x+w <= 0 || y+h <= 0) return 0;
+ Fl_Region r = rstack[rstackptr];
+ if (!r) return 1;
+ // get rid of coordinates outside the 16-bit range the X calls take.
+ if (clip_to_short(x,y,w,h)) return 0; // clipped
+ return XRectInRegion(r, x, y, w, h);
+}
+
+// make there be no clip (used by fl_begin_offscreen() only!)
+void Fl_Xlib_Graphics_Driver::push_no_clip() {
+ if (rstackptr < region_stack_max) rstack[++rstackptr] = 0;
+ else Fl::warning("fl_push_no_cFl_Xlib_Graphics_Driver::push_no_cliplip: clip stack overflow!\n");
+ fl_restore_clip();
+}
+
+// pop back to previous clip:
+void Fl_Xlib_Graphics_Driver::pop_clip() {
+ if (rstackptr > 0) {
+ Fl_Region oldr = rstack[rstackptr--];
+ if (oldr) XDestroyRegion(oldr);
+ } else Fl::warning("Fl_Xlib_Graphics_Driver::pop_clip: clip stack underflow!\n");
+ fl_restore_clip();
+}
+
+void Fl_Xlib_Graphics_Driver::restore_clip() {
+ fl_clip_state_number++;
+ Fl_Region r = rstack[rstackptr];
+ if (r) XSetRegion(fl_display, fl_gc, r);
+ else XSetClipMask(fl_display, fl_gc, 0);
+}
+
+#endif // FL_CFG_GFX_XLIB_RECT_CXX
+
+//
+// End of "$Id$".
+//