hidpi and wayland fixes

libcygnet/src/Window.cc

 void Window::onResize(int w, int h) {
 	w_ = w;
 	h_ = h;
-	glViewport(0, 0, w, h);
+
+	int dw, dh;
+	SDL_GL_GetDrawableSize(state_->window, &dw, &dh);
+	glViewport(0, 0, dw, dh);
 	glCheck();
 }
 

src/main.cc

 
 			case SDL_WINDOWEVENT:
 				if (evt.window.event == SDL_WINDOWEVENT_RESIZED) {
+					window.onResize(evt.window.data1, evt.window.data2);
 					//imguiIO.DisplaySize.x = (float)evt.window.data1;
 					//imguiIO.DisplaySize.y = (float)evt.window.data2;
-					window.onResize(evt.window.data1, evt.window.data2);
 				}
 				break;
 
 				break;
 
 			case SDL_MOUSEWHEEL:
+				if (evt.wheel.y == 0) {
+					break;
+				}
+
 				/*
 				imguiIO.MouseWheel += (float)evt.wheel.y;
 				if (!imguiIO.WantCaptureMouse) */