UI minimally working

watchos2/Module_UI.cpp

@@ -37,11 +37,16 @@ Module_UI::Module_UI()
 	}
 
 	m_root = createWindow(WATCHOS_HANDLE_NULL);
+	m_dirty = true;
+	m_redraw = true;
 }
 
 void Module_UI::tick()
 {
-	draw();
+	if (m_dirty)
+	{
+		draw();
+	}
 }
 
 kernel_handle_t Module_UI::createWindow(IDrawable* drawable, kernel_handle_t parent)
@@ -55,7 +60,7 @@ kernel_handle_t Module_UI::createWindow(IDrawable* drawable, kernel_handle_t par
 			m_window[i]->handle = watchos::kernel()->allocHandle(WATCHOS_HANDLE_TYPE_UI_WINDOW, m_window[i], (kernel_handle_destructor_t)destruct_window);
 			m_window[i]->layout_mode = MODULE_UI_LAYOUT_MODE_NONE;
 			m_window[i]->parent = nullptr;
-			m_window[i]->dirty = false;
+			m_window[i]->dirty = true;
 
 			if (parent != WATCHOS_HANDLE_NULL)
 			{
@@ -93,18 +98,31 @@ kernel_handle_t Module_UI::getRoot()
 
 void Module_UI::draw()
 {
-#ifdef WATCHOS_UI_MULTICORE
-	if (draw_task == nullptr)
+	if (m_dirty)
 	{
-		xTaskCreatePinnedToCore(draw_wrapper, "Draw", MODULE_UI_MULTICORE_STACK_SIZE, this, 0, &draw_task, 0);
-	}
+#ifdef WATCHOS_UI_MULTICORE
+		if (draw_task == nullptr)
+		{
+			// In multi-core mode we clear this _before_ the draw. That way if anything else is marked dirty during
+			// the draw, we'll be primed to do another draw as soon as this one is complete.
+			// Chances are the thing marked dirty may end up drawn during the on-going call anyway (if it hasn't been
+			// drawn yet) and this will generate a extraenous draw, but that's preferable to _not_ drawing an update
+			// and having out-of-date information on the screen.
+			m_dirty = false;
+			xTaskCreatePinnedToCore(draw_wrapper, "Draw", MODULE_UI_MULTICORE_STACK_SIZE, this, 0, &draw_task, 0);
+		}
 #else
-	do_draw();
+		do_draw();
+		// If we're doing synchronous draws then we know everything is now clean once this completes, so we mark that
+		// we don't need another draw.
+		m_dirty = false;
 #endif
+	}
 }
 
 void Module_UI::do_draw()
 {
+	watchos::debug("Draw!");
 	// TODO: Disable light/deep sleep
 
 	// Initialize gfx if necessary
@@ -124,7 +142,12 @@ void Module_UI::do_draw()
 	}
 
 	// TODO: Redraw only parts of the screen if necessary, etc
-	gfx.display(true);
+	// Also confirm that anything was actually drawn. Could mitigate the risk of extraenous draw calls
+	// from multicore (see above comments in draw())
+	// false does a full invert/etc, true just updates in place and can leave ghosting/etc
+	// do false on a full-screen redraw, false otherwise? trigger a full-screen redraw every certain number of redraws?
+	gfx.display(!m_redraw);
+	m_redraw = false;
 
 	// TODO: Reenable sleep
 }
@@ -137,9 +160,10 @@ void Module_UI::draw_window(UiWindow* window, int x, int y, int width, int heigh
 	m_draw_h = height;
 
 	// Draw window
-	if (window->drawable != nullptr)
+	if (window->drawable != nullptr && (window->dirty || m_redraw))
 	{
 		window->drawable->draw(window->handle);
+		window->dirty = false;
 	}
 
 	// Count children
@@ -221,6 +245,7 @@ void Module_UI::setDirty(kernel_handle_t window_handle)
 			return;
 		}
 	}
+	// TODO: Check if window is actually visible before marking m_dirty
 	watchos::panic("Trying to set dirty non-existent window handle: %#010x", window_handle);
 }
 

watchos2/Module_UI.h

@@ -25,7 +25,7 @@ class Module_UI : public Task, public IRunnable
 	UiWindow* m_window[MODULE_UI_MAX_WINDOWS];
 
 	bool m_initialized = false;
-	bool m_dirty = false;
+	bool m_dirty = false, m_redraw = false;
 	// temp, until we implement scenes
 	kernel_handle_t m_root;
 	int m_draw_x, m_draw_y, m_draw_w, m_draw_h;

watchos2/watchos2.ino

@@ -9,7 +9,8 @@
 #include <Preferences.h>
 
 // the setup function runs once when you press reset or power the board
-void setup() {
+void setup()
+{
 	delay(500);
 	watchos::initialize();
 	Kernel* kernel = watchos::kernel();
@@ -21,7 +22,7 @@ void setup() {
 }
 
 // the loop function runs over and over again until power down or reset
-void loop() {
-	watchos::debug("Tick!");
+void loop()
+{	
 	watchos::kernel()->tick();
 }