Add upscale smooth/pixelated option

src/frontend/containers/ContentView/GalleryItem.tsx

@@ -151,12 +151,16 @@ export const Thumbnail = observer(({ file, mounted, forceNoThumbnail }: ItemProp
     return <span className="image-loading" />;
   } else if (imageSource.tag === 'ready') {
     if ('ok' in imageSource.value) {
+      const is_lowres = file.width < 320 || file.height < 320;
       return (
         <img
           src={encodeFilePath(imageSource.value.ok)}
           alt=""
           data-file-id={file.id}
           onError={handleImageError}
+          style={
+            is_lowres && uiStore.upscaleMode == 'pixelated' ? { imageRendering: 'pixelated' } : {}
+          }
         />
       );
     } else {

src/frontend/containers/ContentView/SlideMode/ZoomPan.tsx

@@ -22,6 +22,7 @@ import {
   tryPreventDefault,
   Vec2,
 } from './utils';
+import { UpscaleMode } from '../../../stores/UiStore';
 
 const OVERZOOM_TOLERANCE = 0.05;
 const DOUBLE_TAP_THRESHOLD = 250;
@@ -41,6 +42,7 @@ export interface ZoomPanProps {
   imageDimension: Dimension;
   containerDimension: Dimension;
   onClose?: () => void;
+  upscaleMode: UpscaleMode;
 
   transitionStart?: Transform;
   transitionEnd?: Transform;
@@ -296,7 +298,7 @@ export default class ZoomPan extends React.Component<ZoomPanProps, ZoomPanState>
           onWheel: this.handleMouseWheel,
           onDragStart: tryPreventDefault,
           onContextMenu: tryPreventDefault,
-          style: imageStyle(this.state),
+          style: imageStyle(this.state, this.props.upscaleMode),
         })}
       </div>
     );
@@ -485,9 +487,10 @@ export const CONTAINER_DEFAULT_STYLE = {
   margin: 'auto',
 };
 
-function imageStyle({ top, left, scale }: ZoomPanState): CSSProperties {
+function imageStyle({ top, left, scale }: ZoomPanState, upscaleMode: UpscaleMode): CSSProperties {
   return {
     transform: `translate3d(${Math.trunc(left)}px, ${Math.trunc(top)}px, 0) scale(${scale})`,
+    imageRendering: scale >= 2 && upscaleMode === 'pixelated' ? 'pixelated' : undefined,
   };
 }
 

src/frontend/containers/ContentView/SlideMode/index.tsx

@@ -14,6 +14,7 @@ import { CommandDispatcher } from '../Commands';
 import { ContentRect } from '../utils';
 import ZoomPan, { CONTAINER_DEFAULT_STYLE, SlideTransform } from '../SlideMode/ZoomPan';
 import { createDimension, createTransform, Vec2 } from './utils';
+import { UpscaleMode } from 'src/frontend/stores/UiStore';
 
 const SlideMode = observer(({ contentRect }: { contentRect: ContentRect }) => {
   const { uiStore } = useStore();
@@ -177,6 +178,7 @@ const SlideView = observer(({ width, height }: SlideViewProps) => {
           transitionStart={transitionStart}
           transitionEnd={uiStore.isSlideMode ? undefined : transitionStart}
           onClose={uiStore.disableSlideMode}
+          upscaleMode={uiStore.upscaleMode}
         />
       )}
       <NavigationButtons
@@ -197,6 +199,7 @@ interface ZoomableImageProps {
   transitionStart?: SlideTransform;
   transitionEnd?: SlideTransform;
   onClose: () => void;
+  upscaleMode: UpscaleMode;
 }
 
 const ZoomableImage: React.FC<ZoomableImageProps> = ({
@@ -207,6 +210,7 @@ const ZoomableImage: React.FC<ZoomableImageProps> = ({
   transitionStart,
   transitionEnd,
   onClose,
+  upscaleMode,
 }: ZoomableImageProps) => {
   const { imageLoader } = useStore();
   const { absolutePath, width: imgWidth, height: imgHeight } = file;
@@ -277,6 +281,7 @@ const ZoomableImage: React.FC<ZoomableImageProps> = ({
         transitionStart={transitionStart}
         transitionEnd={transitionEnd}
         onClose={onClose}
+        upscaleMode={upscaleMode}
       >
         {(props) => (
           <img

src/frontend/containers/ContentView/menu-items.tsx

@@ -12,7 +12,7 @@ import {
 import { ClientTag } from 'src/entities/Tag';
 import { useStore } from 'src/frontend/contexts/StoreContext';
 import { IconSet } from 'widgets';
-import { MenuItem, MenuSubItem } from 'widgets/menus';
+import { MenuItem, MenuRadioItem, MenuSubItem } from 'widgets/menus';
 import { LocationTreeItemRevealer } from '../Outliner/LocationsPanel';
 import { TagsTreeItemRevealer } from '../Outliner/TagsPanel/TagsTree';
 import SysPath from 'path';
@@ -160,7 +160,7 @@ export const FileViewerMenuItems = ({ file }: { file: ClientFile }) => {
   );
 };
 
-export const SlideFileViewerMenuItems = ({ file }: { file: ClientFile }) => {
+export const SlideFileViewerMenuItems = observer(({ file }: { file: ClientFile }) => {
   const { uiStore } = useStore();
 
   const handlePreviewWindow = () => {
@@ -175,9 +175,22 @@ export const SlideFileViewerMenuItems = ({ file }: { file: ClientFile }) => {
         text="Open In Preview Window"
         icon={IconSet.PREVIEW}
       />
+
+      <MenuSubItem text="Upscale filtering..." icon={IconSet.VIEW_GRID}>
+        <MenuRadioItem
+          onClick={uiStore.setUpscaleModeSmooth}
+          checked={uiStore.upscaleMode === 'smooth'}
+          text="Smooth"
+        />
+        <MenuRadioItem
+          onClick={uiStore.setUpscaleModePixelated}
+          checked={uiStore.upscaleMode === 'pixelated'}
+          text="Pixelated"
+        />
+      </MenuSubItem>
     </>
   );
-};
+});
 
 export const ExternalAppMenuItems = observer(({ file }: { file: ClientFile }) => {
   const { uiStore } = useStore();

src/frontend/containers/Settings/index.tsx

@@ -86,6 +86,23 @@ const Appearance = observer(() => {
         </fieldset>
       </div>
 
+      <div className="input-group">
+        <RadioGroup name="Picture upscaling">
+          <Radio
+            label="Smooth"
+            checked={uiStore.upscaleMode === 'smooth'}
+            value="smooth"
+            onChange={uiStore.setUpscaleModeSmooth}
+          />
+          <Radio
+            label="Pixelated"
+            checked={uiStore.upscaleMode === 'pixelated'}
+            value="pixelated"
+            onChange={uiStore.setUpscaleModePixelated}
+          />
+        </RadioGroup>
+      </div>
+
       <h3>Thumbnail</h3>
 
       <div className="input-group">

src/frontend/stores/UiStore.ts

@@ -20,6 +20,7 @@ export const enum ViewMethod {
 }
 export type ThumbnailSize = 'small' | 'medium' | 'large' | number;
 type ThumbnailShape = 'square' | 'letterbox';
+export type UpscaleMode = 'smooth' | 'pixelated';
 export const PREFERENCES_STORAGE_KEY = 'preferences';
 
 export interface IHotkeyMap {
@@ -100,6 +101,7 @@ type PersistentPreferenceFields =
   | 'method'
   | 'thumbnailSize'
   | 'thumbnailShape'
+  | 'upscaleMode'
   | 'hotkeyMap'
   | 'isThumbnailTagOverlayEnabled'
   | 'isThumbnailFilenameOverlayEnabled'
@@ -148,6 +150,7 @@ class UiStore {
   @observable firstItem: number = 0;
   @observable thumbnailSize: ThumbnailSize | number = 'medium';
   @observable thumbnailShape: ThumbnailShape = 'square';
+  @observable upscaleMode: UpscaleMode = 'smooth';
 
   @observable isToolbarTagPopoverOpen: boolean = false;
   /** Dialog for removing unlinked files from Allusion's database */
@@ -216,6 +219,14 @@ class UiStore {
     this.setThumbnailShape('letterbox');
   }
 
+  @action.bound setUpscaleModeSmooth() {
+    this.setUpscaleMode('smooth');
+  }
+
+  @action.bound setUpscaleModePixelated() {
+    this.setUpscaleMode('pixelated');
+  }
+
   @action.bound setFirstItem(index: number = 0) {
     if (isFinite(index) && index < this.rootStore.fileStore.fileList.length) {
       this.firstItem = index;
@@ -812,6 +823,9 @@ class UiStore {
         if (prefs.thumbnailShape) {
           this.setThumbnailShape(prefs.thumbnailShape);
         }
+        if (prefs.upscaleMode) {
+          this.setUpscaleMode(prefs.upscaleMode);
+        }
         this.isThumbnailTagOverlayEnabled = Boolean(prefs.isThumbnailTagOverlayEnabled ?? true);
         this.isThumbnailFilenameOverlayEnabled = Boolean(prefs.isThumbnailFilenameOverlayEnabled ?? false); // eslint-disable-line prettier/prettier
         this.isThumbnailResolutionOverlayEnabled = Boolean(prefs.isThumbnailResolutionOverlayEnabled ?? false); // eslint-disable-line prettier/prettier
@@ -866,6 +880,7 @@ class UiStore {
       method: this.method,
       thumbnailSize: this.thumbnailSize,
       thumbnailShape: this.thumbnailShape,
+      upscaleMode: this.upscaleMode,
       hotkeyMap: { ...this.hotkeyMap },
       isThumbnailFilenameOverlayEnabled: this.isThumbnailFilenameOverlayEnabled,
       isThumbnailTagOverlayEnabled: this.isThumbnailTagOverlayEnabled,
@@ -928,6 +943,10 @@ class UiStore {
   @action private setThumbnailShape(shape: ThumbnailShape) {
     this.thumbnailShape = shape;
   }
+
+  @action private setUpscaleMode(mode: UpscaleMode) {
+    this.upscaleMode = mode;
+  }
 }
 
 export default UiStore;