Added readme

README.md

@@ -1 +1,95 @@
-# libtesla
+# libtesla
+
+libtesla is the interface between the Tesla overlay loader and user-made Overlays. It handles all layer creation, UI creation, drawing and input management.
+It's main goal is to make sure all overlays look and feel similar and don't differenciate themselves from the switch's native overlays.
+
+## Screenshots
+
+<div>
+    <img src="./resources/ovl_cheats.jpg" style="width: 50%; float: center">
+    <img src="./resources/ovl_stats.jpg" style="width: 50%; float: right">
+</div>
+
+`Or rather screen pictures. Overlays do NOT show up on Screenshots.`
+
+## Example
+```cpp
+#include <switch.h>
+#include <tesla.hpp>
+
+
+class GuiMain : public tsl::Gui {
+public:
+    GuiMain() { }
+    ~GuiMain() { }
+
+    // Called on UI creation
+    virtual tsl::Element* createUI() {
+        // A base frame containing all other elements
+        auto *rootFrame = new tsl::element::Frame();
+
+        // A CustomDrawer element that allows for direct draw actions to the framebuffer
+        auto *header = new tsl::element::CustomDrawer(0, 0, 100, FB_WIDTH, [](u16 x, u16 y, tsl::Screen *screen) {
+            screen->drawString("Example Overlay", false, 20, 50, 30, tsl::a(0xFFFF));
+        });
+
+        auto list = new tsl::element::List();
+
+        auto testItem = new tsl::element::ListItem("Test List Item");
+        testItem->setClickListener([](s64 keys) {
+            if (keys & KEY_A == KEY_A) {
+                // Do something when key A was pressed while this list item was focused
+
+                // Return true for if this view handled the input
+                return true;
+            }
+
+            return false;
+        });
+
+        // Add list item to list
+        list->addItem(testItem);
+
+        // Add header and list to the frame
+        rootFrame->addElement(header);
+        rootFrame->addElement(list);
+
+        // Return the frame. This will cause it and all its children to be drawn
+        return rootFrame;
+    }
+
+    // Called once per frame
+    virtual void update() { }
+};
+
+class ExampleOverlay : public tsl::Overlay {
+public:
+    ExampleOverlay() { }
+    ~ExampleOverlay() { }
+
+    // Called once right after the overlay was launched
+    tsl::Gui* onSetup() { 
+        // Initialize your services here
+
+        // Return a new Gui object here. This will be the default Gui to be shown when launching the overlay
+        return new GuiMain();
+    }
+
+    // Called once immediately before exiting
+    void onDestroy() { 
+        // Exit your services here
+    }
+
+
+};
+
+
+// This function will get called once on startup to load the overlay
+tsl::Overlay *overlayLoad() {
+    return new ExampleOverlay();
+}
+```
+<br>
+
+**Please Note:** While it is possible to create overlays without libtesla, it's highly recommended to not do so. libtesla handles showing and hiding of overlays, button combo detection, layer creation and a lot more. Not using it will lead to an inconsistent user experience when using multiple different overlays ultimately making it worse for the end user. If something's missing, please consider opening a PR here.
+