WIP - Add Screenshot Capability

Author: olilarkin

.claude/skills/screenshot/SKILL.md

@@ -0,0 +1,85 @@
+---
+name: screenshot
+description: Take a screenshot of an iPlug2 standalone app's GUI for iteration with AI
+---
+
+# Screenshot iPlug2 App GUI
+
+Use this skill to capture a screenshot of a running iPlug2 standalone app. This is useful for iterating on GUI design with AI assistance.
+
+## Requirements
+
+- The app must be built (any configuration works for CLI method)
+- For keyboard/menu methods: the app must be running in **Debug** configuration
+- On first use, macOS may prompt for Screen Recording permission (non-IGraphics builds only)
+
+## Taking a Screenshot
+
+### Method 1: Command Line (Recommended for automation)
+Run the app with `--screenshot <path>`:
+```bash
+./build-ninja/out/TemplateProject.app/Contents/MacOS/TemplateProject --screenshot screenshot.png
+```
+
+The app will launch, render the GUI, save the screenshot, and exit automatically. This method:
+- Skips audio/MIDI initialization for faster startup
+- Works headlessly (no user interaction required)
+- Is ideal for CI/CD and AI-assisted iteration
+
+### Method 2: Keyboard Shortcut
+With the app in focus, press:
+- **macOS:** `Cmd+Shift+S`
+- **Windows:** `Ctrl+Shift+S`
+
+### Method 3: Menu
+1. Open the **Debug** menu
+2. Click **Save Screenshot**
+
+## Screenshot Location
+
+Screenshots are saved to the system temp directory with a timestamp:
+```
+{TMPDIR}/{PluginName}_screenshot_YYYYMMDD_HHMMSS.png
+```
+
+On macOS, `TMPDIR` is typically `/var/folders/.../T/`
+
+After saving, a dialog appears with the full path and an option to open the file.
+
+## Viewing Screenshots in Claude Code
+
+When using the CLI method, the screenshot is saved directly to the specified path:
+```bash
+./MyPlugin.app/Contents/MacOS/MyPlugin --screenshot screenshot.png
+# Then read screenshot.png
+```
+
+For interactive screenshots (keyboard/menu), find the most recent one:
+```bash
+ls -t $TMPDIR/*_screenshot_*.png | head -1
+```
+
+Then ask Claude Code to read the screenshot file.
+
+## Troubleshooting
+
+### No Debug menu visible
+- Ensure the app is built with **Debug** configuration
+- For CMake builds: `cmake -B build -DCMAKE_BUILD_TYPE=Debug`
+- For Xcode builds: Select "Debug" configuration
+
+### Screenshot is blank
+- This can happen with certain GPU-accelerated views
+- The IGraphics-based screenshot (used when IGraphics is available) should work with Metal/NanoVG/Skia backends
+
+### Permission denied on macOS
+- Go to System Preferences > Privacy & Security > Screen Recording
+- Enable permission for the app or Terminal
+
+## Technical Details
+
+The screenshot feature uses:
+- **IGraphics builds:** Layer-based capture via `IGraphics::SaveScreenshot()` - works with all backends
+- **Non-IGraphics builds (Visage, SwiftUI, etc.):** `CGWindowListCreateImage` API via dlsym
+
+Screenshots are captured at full Retina/HiDPI resolution.

TemplateProject/resources/main.rc

@@ -90,6 +90,8 @@ BEGIN
         MENUITEM "&Show Control Bounds\tCtrl+B", ID_SHOW_BOUNDS
         MENUITEM "&Show Drawn Area\tCtrl+D",    ID_SHOW_DRAWN
         MENUITEM "&Show FPS\tCtrl+F",           ID_SHOW_FPS
+        MENUITEM SEPARATOR
+        MENUITEM "&Save Screenshot\tCtrl+Shift+S", ID_SCREENSHOT
     END
     POPUP "&Help"
     BEGIN
@@ -176,6 +178,7 @@ BEGIN
     "D",            ID_SHOW_DRAWN,          VIRTKEY, CONTROL, NOINVERT
     "F",            ID_SHOW_FPS,            VIRTKEY, CONTROL, NOINVERT
     "E",            ID_LIVE_EDIT,           VIRTKEY, CONTROL, NOINVERT
+    "S",            ID_SCREENSHOT,          VIRTKEY, CONTROL, SHIFT, NOINVERT
 END
 
 /////////////////////////////////////////////////////////////////////////////

TemplateProject/resources/main.rc_mac_menu

@@ -10,6 +10,8 @@ SWELL_DEFINE_MENU_RESOURCE_BEGIN(IDR_MENU1)
         MENUITEM "&Show Control Bounds\tCtrl+B", ID_SHOW_BOUNDS
         MENUITEM "&Show Drawn Area\tCtrl+D",    ID_SHOW_DRAWN
         MENUITEM "&Show FPS\tCtrl+F",           ID_SHOW_FPS
+        MENUITEM SEPARATOR
+        MENUITEM "&Save Screenshot\tCtrl+Shift+S", ID_SCREENSHOT
     END
     POPUP "&Help"
     BEGIN

TemplateProject/resources/resource.h

@@ -31,6 +31,7 @@
 #define ID_SHOW_DRAWN                   40026
 #define ID_SHOW_FPS                     40027
 #define ID_SHOW_BOUNDS                  40028
+#define ID_SCREENSHOT                   40029
 
 // Next default values for new objects
 //