From e646939f12a00aa53ad95082d01dbc0493e3d3da Mon Sep 17 00:00:00 2001
From: shogo4405 <shogo4405@gmail.com>
Date: Wed, 24 Jul 2024 00:50:55 +0900
Subject: [PATCH] Fixed a bug where the application crashes when the area is
 large.

---
 Sources/Screen/Screen.swift         |  4 +++-
 Sources/Screen/ScreenObject.swift   | 36 ++++++++++++++++++++++++-----
 Sources/Screen/ScreenRenderer.swift |  7 +++++-
 3 files changed, 39 insertions(+), 8 deletions(-)

diff --git a/Sources/Screen/Screen.swift b/Sources/Screen/Screen.swift
index 9668b0066..eb9f6aca9 100644
--- a/Sources/Screen/Screen.swift
+++ b/Sources/Screen/Screen.swift
@@ -21,6 +21,7 @@ protocol ScreenObserver: AnyObject {
 
 /// An object that manages offscreen rendering a foundation.
 public final class Screen: ScreenObjectContainerConvertible {
+    static let size = CGSize(width: 1280, height: 720)
     private static let lockFrags = CVPixelBufferLockFlags(rawValue: 0)
 
     /// The total of child counts.
@@ -42,11 +43,12 @@ public final class Screen: ScreenObjectContainerConvertible {
     }
 
     /// Specifies the video size to use when output a video.
-    public var size: CGSize = .init(width: 1280, height: 720) {
+    public var size: CGSize = Screen.size {
         didSet {
             guard size != oldValue else {
                 return
             }
+            renderer.bounds = .init(origin: .zero, size: size)
             CVPixelBufferPoolCreate(nil, nil, attributes as CFDictionary?, &pixelBufferPool)
         }
     }
diff --git a/Sources/Screen/ScreenObject.swift b/Sources/Screen/ScreenObject.swift
index 83c2e6c65..26e65c0fd 100644
--- a/Sources/Screen/ScreenObject.swift
+++ b/Sources/Screen/ScreenObject.swift
@@ -153,22 +153,46 @@ public final class ImageScreenObject: ScreenObject {
             guard cgImage != oldValue else {
                 return
             }
-            if let cgImage {
-                size = cgImage.size
-            }
             invalidateLayout()
         }
     }
 
     override public func makeImage(_ renderer: some ScreenRenderer) -> CGImage? {
-        return cgImage
+        let intersection = bounds.intersection(renderer.bounds)
+
+        guard bounds != intersection else {
+            return cgImage
+        }
+
+        // Handling when the drawing area is exceeded.
+        let x: CGFloat
+        switch horizontalAlignment {
+        case .left:
+            x = bounds.origin.x
+        case .center:
+            x = bounds.origin.x / 2
+        case .right:
+            x = 0.0
+        }
+
+        let y: CGFloat
+        switch verticalAlignment {
+        case .top:
+            y = 0.0
+        case .middle:
+            y = abs(bounds.origin.y) / 2
+        case .bottom:
+            y = abs(bounds.origin.y)
+        }
+
+        return cgImage?.cropping(to: .init(origin: .init(x: x, y: y), size: intersection.size))
     }
 
     override public func makeBounds(_ size: CGSize) -> CGRect {
         guard let cgImage else {
-            return super.makeBounds(self.size)
+            return super.makeBounds(size)
         }
-        return super.makeBounds(cgImage.size)
+        return super.makeBounds(size == .zero ? cgImage.size : size)
     }
 }
 
diff --git a/Sources/Screen/ScreenRenderer.swift b/Sources/Screen/ScreenRenderer.swift
index 3d0f5e6b8..ba5315e06 100644
--- a/Sources/Screen/ScreenRenderer.swift
+++ b/Sources/Screen/ScreenRenderer.swift
@@ -9,6 +9,8 @@ public protocol ScreenRenderer: AnyObject {
     var context: CIContext { get }
     /// Specifies the backgroundColor for output video.
     var backgroundColor: CGColor { get set }
+    /// The current screen bounds.
+    var bounds: CGRect { get }
     /// Layouts a screen object.
     func layout(_ screenObject: ScreenObject)
     /// Draws a sceen object.
@@ -18,6 +20,8 @@ public protocol ScreenRenderer: AnyObject {
 }
 
 final class ScreenRendererByCPU: ScreenRenderer {
+    var bounds: CGRect = .init(origin: .zero, size: Screen.size)
+
     lazy var context = {
         guard let deive = MTLCreateSystemDefaultDevice() else {
             return CIContext(options: nil)
@@ -142,7 +146,8 @@ final class ScreenRendererByCPU: ScreenRenderer {
         }
 
         let origin = screenObject.bounds.origin
-        let start = Int(origin.y) * canvas.rowBytes + Int(origin.x) * 4
+        let start = Int(max(0, origin.y)) * canvas.rowBytes + Int(max(0, origin.x)) * 4
+
         var destination = vImage_Buffer(
             data: canvas.data.advanced(by: start),
             height: image.height,