Finished implementing mouse events on GTK+ uiArea.

gtkarea/area.c

@@ -175,7 +175,7 @@ static uiModifiers toModifiers(guint state)
 	uiModifiers m;
 
 	m = 0;
-	if ((state & GDK_CONTROL_MASK) != 0))
+	if ((state & GDK_CONTROL_MASK) != 0)
 		m |= uiModifierCtrl;
 	if ((state & GDK_META_MASK) != 0)
 		m |= uiModifierAlt;
@@ -280,7 +280,7 @@ static gboolean areaWidget_motion_notify_event(GtkWidget *w, GdkEventMotion *e)
 // we want switching away from the control to reset the double-click counter, like with WM_ACTIVATE on Windows
 // according to tristan in irc.gimp.net/#gtk+, doing this on enter-notify-event and leave-notify-event is correct (and it seems to be true in my own tests; plus the events DO get sent when switching programs with the keyboard (just pointing that out))
 // differentiating between enter-notify-event and leave-notify-event is unimportant
-gboolean areaWidget_enterleave_notify_event(GtkWidget *widget, GdkEventCrossing *e)
+gboolean areaWidget_enterleave_notify_event(GtkWidget *w, GdkEventCrossing *e)
 {
 	struct areaPrivate *ap = areaWidget(w)->priv;
 

gtkarea/area.h

@@ -28,6 +28,7 @@ struct areaWidgetClass {
 extern GType areaWidget_get_type(void);
 
 #include "ui.h"
+#include "uipriv.h"
 
 extern GtkWidget *newArea(uiAreaHandler *ah);
 extern void areaUpdateScroll(GtkWidget *area);

gtkarea/events.c

@@ -0,0 +1,161 @@
+// 29 march 2014
+// TODO remove
+#include <stdint.h>
+#include "ui.h"
+#include "uipriv.h"
+
+/*
+Windows and GTK+ have a limit of 2 and 3 clicks, respectively, natively supported. Fortunately, we can simulate the double/triple-click behavior to build higher-order clicks. We can use the same algorithm Windows uses on both:
+	http://blogs.msdn.com/b/oldnewthing/archive/2004/10/18/243925.aspx
+For GTK+, we pull the double-click time and double-click distance, which work the same as the equivalents on Windows (so the distance is in all directions), from the GtkSettings system.
+
+On GTK+ this will also allow us to discard the GDK_BUTTON_2PRESS and GDK_BUTTON_3PRESS events, so the button press stream will be just like on other platforms.
+
+Thanks to mclasen, garnacho_, halfline, and tristan in irc.gimp.net/#gtk+.
+*/
+
+// x, y, xdist, ydist, and c.rect must have the same units
+// so must time, maxTime, and c.prevTime
+uintmax_t clickCounterClick(clickCounter *c, uintmax_t button, intmax_t x, intmax_t y, uintptr_t time, uintptr_t maxTime, intmax_t xdist, intmax_t ydist)
+{
+	// different button than before? if so, don't count
+	if (button != c->curButton)
+		c->count = 0;
+
+	// (x, y) in the allowed region for a double-click? if not, don't count
+	if (x < c->rectX0)
+		c->count = 0;
+	if (y < c->rectY0)
+		c->count = 0;
+	if (x >= c->rectX1)
+		c->count = 0;
+	if (y >= c->rectY1)
+		c->count = 0;
+
+	// too slow? if so, don't count
+	// note the below expression; time > (c.prevTime + maxTime) can overflow!
+	if ((time - c->prevTime) > maxTime)	// too slow; don't count
+		c->count = 0;
+
+	c->count++;		// if either of the above ifs happened, this will make the click count 1; otherwise it will make the click count 2, 3, 4, 5, ...
+
+	// now we need to update the internal structures for the next test
+	c->curButton = button;
+	c->prevTime = time;
+	c->rectX0 = x - xdist;
+	c->rectY0 = y - ydist;
+	c->rectX1 = x + xdist;
+	c->rectY1 = y + ydist;
+
+	return c->count;
+}
+
+void clickCounterReset(clickCounter *c)
+{
+	c->curButton = 0;
+	c->rectX0 = 0;
+	c->rectY0 = 0;
+	c->rectX1 = 0;
+	c->rectY1 = 0;
+	c->prevTime = 0;
+	c->count = 0;
+}
+
+/*
+For position independence across international keyboard layouts, typewriter keys are read using scancodes (which are always set 1).
+Windows provides the scancodes directly in the LPARAM.
+GTK+ provides the scancodes directly from the underlying window system via GdkEventKey.hardware_keycode.
+On X11, this is scancode + 8 (because X11 keyboard codes have a range of [8,255]).
+Wayland is guaranteed to give the same result (thanks ebassi in irc.gimp.net/#gtk+).
+On Linux, where evdev is used instead of polling scancodes directly from the keyboard, evdev's typewriter section key code constants are the same as scancodes anyway, so the rules above apply.
+Typewriter section scancodes are the same across international keyboards with some exceptions that have been accounted for (see KeyEvent's documentation); see http://www.quadibloc.com/comp/scan.htm for details.
+Non-typewriter keys can be handled safely using constants provided by the respective backend API.
+
+Because GTK+ keysyms may or may not obey Num Lock, we also handle the 0-9 and . keys on the numeric keypad with scancodes (they match too).
+*/
+
+/*
+TODO
+
+// use uintptr to be safe; the size of the scancode/hardware key code field on each platform is different
+var scancodeKeys = map[uintptr]byte{
+	0x02: '1',
+	0x03: '2',
+	0x04: '3',
+	0x05: '4',
+	0x06: '5',
+	0x07: '6',
+	0x08: '7',
+	0x09: '8',
+	0x0A: '9',
+	0x0B: '0',
+	0x0C: '-',
+	0x0D: '=',
+	0x0E: '\b',
+	0x0F: '\t',
+	0x10: 'q',
+	0x11: 'w',
+	0x12: 'e',
+	0x13: 'r',
+	0x14: 't',
+	0x15: 'y',
+	0x16: 'u',
+	0x17: 'i',
+	0x18: 'o',
+	0x19: 'p',
+	0x1A: '[',
+	0x1B: ']',
+	0x1C: '\n',
+	0x1E: 'a',
+	0x1F: 's',
+	0x20: 'd',
+	0x21: 'f',
+	0x22: 'g',
+	0x23: 'h',
+	0x24: 'j',
+	0x25: 'k',
+	0x26: 'l',
+	0x27: ';',
+	0x28: '\'',
+	0x29: '`',
+	0x2B: '\\',
+	0x2C: 'z',
+	0x2D: 'x',
+	0x2E: 'c',
+	0x2F: 'v',
+	0x30: 'b',
+	0x31: 'n',
+	0x32: 'm',
+	0x33: ',',
+	0x34: '.',
+	0x35: '/',
+	0x39: ' ',
+}
+
+var scancodeExtKeys = map[uintptr]ExtKey{
+	0x47: N7,
+	0x48: N8,
+	0x49: N9,
+	0x4B: N4,
+	0x4C: N5,
+	0x4D: N6,
+	0x4F: N1,
+	0x50: N2,
+	0x51: N3,
+	0x52: N0,
+	0x53: NDot,
+}
+
+func fromScancode(scancode uintptr) (ke KeyEvent, ok bool) {
+	if key, ok := scancodeKeys[scancode]; ok {
+		ke.Key = key
+		return ke, true
+	}
+	if extkey, ok := scancodeExtKeys[scancode]; ok {
+		ke.ExtKey = extkey
+		return ke, true
+	}
+	return ke, false
+}
+
+*/

gtkarea/main.c

@@ -104,6 +104,20 @@ static int handlerRedrawOnResize(uiAreaHandler *a, uiArea *area)
 	return 1;
 }
 
+static void handlerMouseEvent(uiAreaHandler *a, uiArea *area, uiAreaMouseEvent *e)
+{
+	printf("mouse (%d,%d):(%d,%d) dn:%d up:%d count:%d mods:%x held:%x\n",
+		(int) e->X,
+		(int) e->Y,
+		(int) e->HScrollPos,
+		(int) e->VScrollPos,
+		(int) e->Down,
+		(int) e->Up,
+		(int) e->Count,
+		(uint32_t) e->Modifiers,
+		e->Held1To64);
+}
+
 static void recalcScroll(GtkSpinButton *sb, gpointer data)
 {
 	areaUpdateScroll(area);
@@ -130,6 +144,7 @@ int main(void)
 	h.ah.HScrollMax = handlerHScrollMax;
 	h.ah.VScrollMax = handlerVScrollMax;
 	h.ah.RedrawOnResize = handlerRedrawOnResize;
+	h.ah.MouseEvent = handlerMouseEvent;
 
 	gtk_init(NULL, NULL);
 

gtkarea/ui.h

@@ -138,6 +138,8 @@ struct uiAreaMouseEvent {
 	uintmax_t Down;
 	uintmax_t Up;
 
+	uintmax_t Count;
+
 	uiModifiers Modifiers;
 
 	uint64_t Held1To64;

gtkarea/uipriv.h

@@ -0,0 +1,14 @@
+typedef struct clickCounter clickCounter;
+// you should call Reset() to zero-initialize a new instance
+// it doesn't matter that all the non-count fields are zero: the first click will fail the curButton test straightaway, so it'll return 1 and set the rest of the structure accordingly
+struct clickCounter {
+	uintmax_t curButton;
+	intmax_t rectX0;
+	intmax_t rectY0;
+	intmax_t rectX1;
+	intmax_t rectY1;
+	uintptr_t prevTime;
+	uintmax_t count;
+};
+extern uintmax_t clickCounterClick(clickCounter *, uintmax_t, intmax_t, intmax_t, uintptr_t, uintptr_t, intmax_t, intmax_t);
+extern void clickCounterReset(clickCounter *);