Create custom-layers.md, update utils.md, and Create chap4_2

handbook/vol4/chap4_2.md

@@ -0,0 +1,32 @@
+# Chapter 4.2: Searching through the docs
+
+At some point or another, you will need to find a class to hook or a function to call. This chapter explains how to search through the Geode classes tab.
+
+## Seaching for classes
+Geode docs have a useful "classes" tab to search for classes. If you do not know what class something is, it is best to search through [DevTools](https://github.com/geode-sdk/DevTools) first, then search it up the docs. However, if devtools does not tell you the classname, then you would have to find the class yourself.
+
+## I found a class! What now?
+Congrats! You can now hook the object by copying the signiture of the function! [Geode's vscode](https://marketplace.visualstudio.com/items?itemName=GeodeSDK.geode) extension provides autocomplete for function signatures, so it is recommended to use that.
+
+## But what if I want to get said object from another object?
+Most objects have either a `::get()` or a `::sharedState()` (or even both [Note 1]!) static function. Most of the time, this function will return the object, however if the object does not exist, it will return a nullptr.
+c++ lets you check if an object is nullptr and run code if it does exist.
+
+```cpp
+if (auto level = GJBaseGameLayer::get()) {
+	// This code will only run if you are in a level
+	// level is a pointer to your current level
+}
+
+else {
+	// Otherwise, run this code.
+}
+```
+
+If the object does not have a `::get()` method, you would need to find another way to get it.
+
+> :warning: Enums do not appear in the search! You would need to find them some other way!
+
+> :warning: Some functions may be inlined on some platforms! Hooking them would cause a compilation error. You would need to find some other function to hook.
+
+> [Note 1] `::get()` and `::sharedState()` methods act the **exact same** on most classes with both of them

tutorials/custom-layers.md

@@ -0,0 +1,180 @@
+# Custom Layers
+
+At some point a modder may want to create a custom layer for their mod, for one reason or another.
+
+
+Creating a new scene is easy. You must create a new class extending `cocos2d:::CCLayer`, and add additional UI (such as buttons, popups, or even a level) by overriding the the `*::init` function.
+
+```cpp
+class MyVeryOriginalLayer : public CCLayer {
+protected:
+    bool init() override {
+
+        if (!CCLayer::init()) {
+            // Something very bad happened
+            return false;
+        }
+
+        log::info("Hi from my very original layer");
+        return true;
+    }
+
+public:
+    static MyVeryOriginalLayer* create() {
+        auto ret = new MyVeryOriginalLayer;
+        if (ret->init()) {
+            ret->autorelease();
+            return ret;
+        }
+        delete ret;
+        return nullptr;
+    }
+}
+```
+
+This code will create a new layer called MyVeryOriginalLayer. When we start up the game, we will not see the layer as we do transition to it. Calling `MyVeryOriginalLayer::create()` will not transition to the layer, as it only creates it, not replaces the current layer. To be able to transition to the layer, we can use `switchToScene(layer)`. We can create a static function to easily create and switch to the scene:
+
+```cpp
+static MyVeryOriginalLayer* scene() {
+    auto layer = MyVeryOriginalLayer::create();
+    switchToScene(layer);
+    return layer;
+}
+```
+
+## UI
+
+Running this code and calling `MyVeryOriginalLayer::scene()` will transition the current scene to MyVeryOriginalLayer, however it is currently very barren. Geode provides utility functions to create background and side art.
+
+```
+#include <Geode/ui/General.hpp>
+
+bool init() override {
+    log::info("Hi from my very original layer");
+
+    // Create a new menu. UI Buttons should be added to here.
+    auto menu = CCMenu::create();
+
+    // Using geode's built in utils for creating side art and background makes it easier for other mods to modify & change them.
+    // It is recommended to use these instead of manually adding them some other way.
+
+    // Add side art to the layer
+    geode::addSideArt(this, SideArt::All, SideArtStyle::Layer);
+
+    // And a background to the layer
+    auto background = geode::createLayerBG();
+    background->setID("background");
+    this->addChild(background);	
+    return true;
+}
+```
+
+The rest of the buttons and UI can be created the same way you would in a hook.
+
+> :warning: Button elements must be in CCMenu object!
+
+
+## Back button
+
+Now the biggest problem with this layer is that you are stuck in it. To go back you would want to create a button whose callback transitions to another scene. 
+
+```cpp
+
+bool init() override {
+    // Create a back button with the back button sprites
+    auto backBtn = CCMenuItemSpriteExtra::create(
+        CCSprite::createWithSpriteFrameName("GJ_arrow_01_001.png"),
+        this,
+        menu_selector(MyVeryOriginalLayer::onBack)
+    );
+
+    // Not adding this function will disable keyBackClicked from being called.
+    // This makes it impossible to exit levels with the backspace key.
+    this->setKeypadEnabled(true);
+
+    // Add a back button the the top-left corner of the screen with a small offset.
+    menu->addChildAtPosition(backBtn, Anchor::TopLeft, {25, -25});
+    this->addChild(menu);
+    return true;
+}
+
+// This function is called when the escape key is pressed!
+void keyBackClicked() override {
+    this->onBack(nullptr);
+}
+
+void onBack(CCObject* sender) {
+    CCDirector::get()->replaceScene(CCTransitionFade::create(0.5, MenuLayer::scene()));
+}
+
+```
+
+> :information_source: You can also create a back button with `GameToolbox::addBackButton`
+
+> :warning: Pressing escape will **not transition the layer** back unless you override `keyBackClicked()`!
+
+
+
+## Example
+
+This code will transition to the MyVeryOriginalLayer when clicking the on more games button.
+
+```cpp
+#include <Geode/Geode.hpp>
+#include <Geode/ui/General.hpp>
+#include <Geode/modify/MenuLayer.hpp>
+using namespace geode::prelude;
+
+class MyVeryOriginalLayer : public CCLayer {
+protected:
+    bool init() override {
+        log::info("Hi from my very original layer");
+
+        // Create a new menu. UI elemnts should be added to here!
+        menu = CCMenu::create();
+
+        // Add side art to the layer
+        addSideArt(this, SideArt::All, SideArtStyle::Layer);
+
+        // And a background to the layer
+        auto background = createLayerBG();
+        background->setID("background");
+        this->addChild(background);	
+    return true;
+    }
+
+    // This function is called when the escape key is pressed!
+    void keyBackClicked() override {
+        this->onBack(nullptr);
+    }
+
+public:
+    static MyVeryOriginalLayer* create() {
+        auto ret = new MyVeryOriginalLayer;
+        if (ret->init()) {
+            ret->autorelease();
+            return ret;
+        }
+        CC_SAFE_DELETE(ret);
+        return nullptr;
+    }
+
+    static MyVeryOriginalLayer* MyVeryOriginalLayer::scene() {
+        auto layer = MyVeryOriginalLayer::create();
+        switchToScene(layer);
+        return layer;
+    }
+
+
+    void onBack(CCObject* sender) {
+        CCDirector::get()->replaceScene(CCTransitionFade::create(0.5, MenuLayer::scene()));
+    }
+
+}
+
+class $modify(MenuLayer) {
+    void onMoreGames(CCObject* target) {
+        MyVeryOriginalLayer::scene();
+    }
+};
+```

tutorials/utils.md

@@ -109,6 +109,27 @@ auto hook1 = GEODE_UNWRAP(ObjcHook::create("EAGLView", "initWithFrame:", &MyFunc
 auto hook2 = GEODE_UNWRAP(ObjcHook::create("EAGLView", "initWithFrame:", &MyFunc, &emptyFunc));
 ```
 
+### geode::dirs
+
+```cpp
+// This is where geode is located!
+auto geodeDir = dirs::getGeodeDir();
+
+// This is where geodes resources are stored!
+auto geodeResourcesDir = dirs::getGeodeResourcesDir();
+
+// This is where geodes saves its files!
+auto geodeSaveDir = dirs::getGeodeSaveDir();
+
+// This is where mod's save files are!
+auto modSaveDir = dirs::getModsSaveDir();
+
+// This is where GD saves its files!
+auto saveDir = dirs::getSaveDir();
+
+// Other directories also exist
+```
+
 ## Tasks
 
 Visit the [tasks](tasks.md) page for more information.
@@ -304,4 +325,4 @@ timePointAsString`
 
 ### ColorProvider
 
-No idea how to use this one.
+No idea how to use this one.