refactor: clean up

Memola/Canvas/Core/Canvas.swift

@@ -19,7 +19,7 @@ final class Canvas: ObservableObject, Identifiable, @unchecked Sendable {
     let viewPortContext = ViewPortContext()
 
     let maximumZoomScale: CGFloat = 35
-    let minimumZoomScale: CGFloat = 5
+    let minimumZoomScale: CGFloat = 8
     let defaultZoomScale: CGFloat = 20
 
     var transform: simd_float4x4 = .init()

Memola/Canvas/Elements/Core/Element.swift

@@ -45,7 +45,11 @@ enum Element: Equatable, Comparable {
         switch self {
         case .stroke(let anyStroke):
             switch anyStroke.value.style {
-            case .marker: return .stroke
+            case .marker: 
+                guard let penStroke = anyStroke.stroke(as: PenStroke.self) else {
+                    return .stroke(penStyle: .marker, color: [0, 0, 0, 0])
+                }
+                return .stroke(penStyle: penStroke.penStyle, color: penStroke.color)
             case .eraser: return .eraser
             }
         case .photo:

Memola/Canvas/Elements/Core/ElementGroup.swift

@@ -28,15 +28,15 @@ class ElementGroup {
     }
 
     func getPenStyle() -> PenStyle? {
-        if let last = elements.last, case let .stroke(anyStroke) = last {
+        if case let .stroke(penStyle, _) = type {
-            return anyStroke.value.penStyle
+            return penStyle
         }
         return nil
     }
 
     func getPenColor() -> [CGFloat]? {
-        if let last = elements.last, case let .stroke(anyStroke) = last {
+        if case let .stroke(_, color) = type {
-            return anyStroke.value.color
+            return color
         }
         return nil
     }
@@ -44,7 +44,7 @@ class ElementGroup {
 
 extension ElementGroup {
     enum ElementGroupType {
-        case stroke
+        case stroke(penStyle: PenStyle, color: [CGFloat])
         case eraser
         case photo
     }

Memola/Canvas/Elements/Geometries/Stroke/Core/Stroke.swift

@@ -8,7 +8,7 @@
 import MetalKit
 import Foundation
 
-protocol Stroke: AnyObject, Drawable, Hashable, Equatable {
+protocol Stroke: AnyObject, Hashable, Equatable {
     var id: UUID { get set }
     var bounds: [CGFloat] { get set }
     var color: [CGFloat] { get set }
@@ -80,31 +80,6 @@ extension Stroke {
     }
 }
 
-extension Stroke {
-    func prepare(device: MTLDevice) {
-        guard texture == nil else { return }
-        if penStyle.textureName != nil {
-            texture = penStyle.loadTexture(on: device)
-        }
-    }
-
-    func draw(device: MTLDevice, renderEncoder: MTLRenderCommandEncoder) {
-        guard !isEmpty, let indexBuffer else { return }
-        prepare(device: device)
-        if penStyle.textureName != nil {
-            renderEncoder.setFragmentTexture(texture, index: 0)
-        }
-        renderEncoder.setVertexBuffer(vertexBuffer, offset: 0, index: 0)
-        renderEncoder.drawIndexedPrimitives(
-            type: .triangle,
-            indexCount: quads.endIndex * 6,
-            indexType: .uint32,
-            indexBuffer: indexBuffer,
-            indexBufferOffset: 0
-        )
-    }
-}
-
 extension Stroke {
     static func == (lhs: Self, rhs: Self) -> Bool {
         lhs.id == rhs.id

Memola/Canvas/Elements/Geometries/Stroke/Strokes/PenStroke.swift

@@ -152,20 +152,4 @@ final class PenStroke: Stroke, @unchecked Sendable {
     func getAllErasedQuads() -> [Quad] {
         eraserStrokes.flatMap { $0.quads }
     }
-
-    func erase(device: MTLDevice, renderEncoder: MTLRenderCommandEncoder) {
-        guard !isEmptyErasedQuads, let erasedIndexBuffer else {
-            return
-        }
-        prepare(device: device)
-        renderEncoder.setFragmentTexture(texture, index: 0)
-        renderEncoder.setVertexBuffer(erasedVertexBuffer, offset: 0, index: 0)
-        renderEncoder.drawIndexedPrimitives(
-            type: .triangle,
-            indexCount: erasedQuadCount * 6,
-            indexType: .uint32,
-            indexBuffer: erasedIndexBuffer,
-            indexBufferOffset: 0
-        )
-    }
 }

Memola/Canvas/View/Bridge/Views/DrawingView.swift

@@ -32,7 +32,7 @@ class DrawingView: UIView {
     }
 
     func updateDrawableSize(with size: CGSize) {
-        renderView.drawableSize = size.multiply(by: 2.6)
+        renderView.drawableSize = size.multiply(by: 2)
     }
 
     override func gestureRecognizerShouldBegin(_ gestureRecognizer: UIGestureRecognizer) -> Bool {