Add mouse wheel events and wheel zoom in modelview

2 files changed, 54 insertions, 1 deletions

diff --git a/kon/kondebug.c b/kon/kondebug.c
index a905adc..a68ebcf 100644
--- a/kon/kondebug.c
+++ b/kon/kondebug.c
@@ -541,6 +541,12 @@ int kon_debugFeedEvent(kon_debug_t *d, const kon_event_t *e)
 		if (e->codepoint >= 32 && e->codepoint <= 126) kon_debugInsert_(d, (char)e->codepoint);
 		return 1;
 	}
+	if (e->type == KON_EVENT_MOUSE_WHEEL) {
+		d->scroll += e->wheel * 3;
+		if (d->scroll < 0) d->scroll = 0;
+		if (d->scroll > d->logCount - 1) d->scroll = d->logCount > 0 ? d->logCount - 1 : 0;
+		return 1;
+	}
 	if (e->type == KON_EVENT_KEY_UP) return 1;
 	if (e->type != KON_EVENT_KEY_DOWN) return 0;
 
diff --git a/kon/konwinlib.h b/kon/konwinlib.h
index 6e2ad5a..0a1f365 100644
--- a/kon/konwinlib.h
+++ b/kon/konwinlib.h
@@ -62,7 +62,8 @@ typedef enum kon_eventType {
 	KON_EVENT_MOUSE_DOWN,
 	KON_EVENT_MOUSE_UP,
 	KON_EVENT_MOUSE_MOVE,
-	KON_EVENT_TEXT
+	KON_EVENT_TEXT,
+	KON_EVENT_MOUSE_WHEEL
 } kon_eventType_t;
 
 typedef enum kon_mouseButton {
@@ -110,6 +111,7 @@ typedef struct kon_event {
 	unsigned int codepoint; /* unicode codepoint, only set for KON_EVENT_TEXT */
 	int mouseX, mouseY;
 	kon_mouseButton_t mouseButton;
+	int wheel; /* only set for KON_EVENT_MOUSE_WHEEL, 1 for each notch away from you and -1 towards you */
 } kon_event_t;
 
 kon_window_t *kon_createWindow(const char *title, int x, int y, int width, int height, kon_windowFlags_t flags);
@@ -380,6 +382,21 @@ static EM_BOOL kon_mouseCallback_(int eventType, const EmscriptenMouseEvent *e,
 	return EM_TRUE;
 }
 
+static EM_BOOL kon_wheelCallback_(int eventType, const EmscriptenWheelEvent *e, void *userData) {
+	kon_window_t *window = (kon_window_t *)userData;
+	kon_event_t ev = {0};
+
+	(void)eventType;
+	if (e->deltaY == 0.0) return EM_FALSE;
+	ev.type = KON_EVENT_MOUSE_WHEEL;
+	ev.wheel = e->deltaY < 0.0 ? 1 : -1;
+	ev.mouseX = (int)e->mouse.targetX;
+	ev.mouseY = (int)e->mouse.targetY;
+	kon_pushEvent_(&window->queue, &ev);
+
+	return EM_TRUE;
+}
+
 kon_window_t *kon_createWindow(const char *title, int x, int y, int width, int height, kon_windowFlags_t flags) {
 	(void)x; (void)y; (void)flags;
 
@@ -406,6 +423,7 @@ kon_window_t *kon_createWindow(const char *title, int x, int y, int width, int h
 	emscripten_set_mousedown_callback(window->canvasID, window, EM_FALSE, kon_mouseCallback_);
 	emscripten_set_mouseup_callback(window->canvasID, window, EM_FALSE, kon_mouseCallback_);
 	emscripten_set_mousemove_callback(window->canvasID, window, EM_FALSE, kon_mouseCallback_);
+	emscripten_set_wheel_callback(window->canvasID, window, EM_FALSE, kon_wheelCallback_);
 
 	return window;
 }
@@ -419,6 +437,7 @@ void kon_destroyWindow(kon_window_t *window) {
 	emscripten_set_mousedown_callback(window->canvasID, NULL, EM_FALSE, NULL);
 	emscripten_set_mouseup_callback(window->canvasID, NULL, EM_FALSE, NULL);
 	emscripten_set_mousemove_callback(window->canvasID, NULL, EM_FALSE, NULL);
+	emscripten_set_wheel_callback(window->canvasID, NULL, EM_FALSE, NULL);
 
 	free(window);
 }
@@ -948,6 +967,17 @@ static void kon_pumpX11_(kon_window_t *window) {
 			case Button1: ev.mouseButton = KON_MOUSE_LEFT; break;
 			case Button2: ev.mouseButton = KON_MOUSE_MIDDLE; break;
 			case Button3: ev.mouseButton = KON_MOUSE_RIGHT; break;
+			case Button4:
+			case Button5:
+				/* the wheel shows up as button 4 and 5 being pressed, the release is not interesting */
+				if (xev.type == ButtonPress) {
+					ev.type = KON_EVENT_MOUSE_WHEEL;
+					ev.wheel = xev.xbutton.button == Button4 ? 1 : -1;
+					ev.mouseX = xev.xbutton.x;
+					ev.mouseY = xev.xbutton.y;
+					kon_pushEvent_(&window->queue, &ev);
+				}
+				continue;
 			default: continue;
 			}
 			ev.type = (xev.type == ButtonPress) ? KON_EVENT_MOUSE_DOWN : KON_EVENT_MOUSE_UP;
@@ -1635,6 +1665,23 @@ LRESULT CALLBACK kon_wndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
 			kon_pushEvent_(&window->queue, &ev);
 		}
 		break;
+	case WM_MOUSEWHEEL:
+		if (window) {
+			kon_event_t ev = {0};
+			POINT point;
+			int delta = (int)(short)HIWORD(wParam);
+
+			if (delta == 0) break;
+			point.x = (int)(short)LOWORD(lParam);
+			point.y = (int)(short)HIWORD(lParam);
+			ScreenToClient(hwnd, &point);
+			ev.type = KON_EVENT_MOUSE_WHEEL;
+			ev.wheel = delta > 0 ? 1 : -1;
+			ev.mouseX = (int)point.x;
+			ev.mouseY = (int)point.y;
+			kon_pushEvent_(&window->queue, &ev);
+		}
+		break;
 	case WM_MOUSEMOVE:
 		if (window) {
 			kon_event_t ev = {0};