Initial revision

git-svn-id: file:///fltk/svn/fltk/trunk@2 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

1 files changed, 78 insertions, 0 deletions

diff --git a/src/Fl_visual.cxx b/src/Fl_visual.cxx
new file mode 100644
index 000000000..d45c3ed49
--- /dev/null
+++ b/src/Fl_visual.cxx
@@ -0,0 +1,78 @@
+// Fl_visual.C
+//
+// Set the default visual according to passed switches:
+
+#include <config.h>
+#include <FL/Fl.H>
+#include <FL/x.H>
+
+#ifdef WIN32
+int Fl::visual(int flags) {
+  if (flags & FL_DOUBLE) return 0;
+  if (!(flags & FL_INDEX) &&
+    GetDeviceCaps(fl_GetDC(0),BITSPIXEL) <= 8) return 0;
+  if ((flags & FL_RGB8) && GetDeviceCaps(fl_GetDC(0),BITSPIXEL)<24) return 0;
+  return 1;
+}
+#else
+
+#if USE_XDBE
+#include <X11/extensions/Xdbe.h>
+#endif
+
+static int test_visual(XVisualInfo& v, int flags) {
+  if (v.screen != fl_screen) return 0;
+  if (!(flags & FL_INDEX)) {
+    if (!v.red_mask) return 0; // detects static, true, and direct color
+    if (v.depth <= 8) return 0; // fltk will work better in colormap mode
+  }
+  if (flags & FL_RGB8) {
+    if (v.depth < 24) return 0;
+  }
+  // for now, fltk does not like colormaps of more than 8 bits:
+  if (!v.red_mask && v.depth > 8) return 0;
+#if USE_XDBE
+  if (flags & FL_DOUBLE) {
+    static XdbeScreenVisualInfo *xdbejunk;
+    if (!xdbejunk) {
+      int event_base, error_base;
+      if (!XdbeQueryExtension(fl_display, &event_base, &error_base)) return 0;
+      Drawable root = RootWindow(fl_display,fl_screen);
+      int numscreens = 1;
+      xdbejunk = XdbeGetVisualInfo(fl_display,&root,&numscreens);
+      if (!xdbejunk) return 0;
+    }
+    for (int j = 0; ; j++) {
+      if (j >= xdbejunk->count) return 0;
+      if (xdbejunk->visinfo[j].visual == v.visualid) break;
+    }
+  }
+#endif
+  return 1;
+}
+
+int Fl::visual(int flags) {
+#if USE_XDBE == 0
+  if (flags & FL_DOUBLE) return 0;
+#endif
+  fl_open_display();
+  // always use default if possible:
+  if (test_visual(*fl_visual, flags)) return 1;
+  // get all the visuals:
+  XVisualInfo vTemplate;
+  int num;
+  XVisualInfo *visualList = XGetVisualInfo(fl_display, 0, &vTemplate, &num);
+  // find all matches, use the one with greatest depth:
+  XVisualInfo *found = 0;
+  for (int i=0; i<num; i++) if (test_visual(visualList[i], flags)) {
+    if (!found || found->depth < visualList[i].depth)
+      found = &visualList[i];
+  }
+  if (!found) {XFree((void*)visualList); return 0;}
+  fl_visual = found;
+  fl_colormap = XCreateColormap(fl_display, RootWindow(fl_display,fl_screen),
+				fl_visual->visual, AllocNone);
+  return 1;
+}
+
+#endif