Add WIP palette support

frontend/src/App.svelte

@@ -9,7 +9,7 @@
   import { LoadedFile, PixelsPlaceUndoable, SelectionClearUndoable, SelectionSetUndoable } from './types/file'
 
   import "carbon-components-svelte/css/all.css"
-  import { Tabs, Tab, TabContent, Theme, Button, Modal, Truncate, ButtonSet, NumberInput } from "carbon-components-svelte"
+  import { Tabs, Tab, TabContent, Theme, Button, Modal, Truncate, ButtonSet, NumberInput, Dropdown } from "carbon-components-svelte"
   import { ComposedModal } from "carbon-components-svelte"
   
   import { OverflowMenu, OverflowMenuItem } from "carbon-components-svelte"
@@ -44,6 +44,23 @@
   let alpha: number = 0
 
   let refreshPalette = {}
+  let fakePalette: Uint32Array | undefined = undefined
+  let selectedPaletteID: number = 0
+  $: {
+    if (selectedPaletteID === 0) {
+      fakePalette = undefined
+    } else if (selectedPaletteID === 1) {
+      fakePalette = new Uint32Array([
+        0xFFE0F8D0, 0xFF88C070, 0xFF346856, 0xFF081820,
+        0xFFF8F8F8, 0xFFC0C0C0, 0xFF606060, 0xFF202020,
+        0xFFF8D8F8, 0xFFA800A8, 0xFF503050, 0xFF200020,
+        0xFFF8B8F8, 0xFFA800A8, 0xFF503050, 0xFF200020,
+      ])
+    }
+    focusedFile?.canvas.setFakePalette(fakePalette)
+    focusedFile?.canvas.refreshImageData()
+    focusedFile?.canvas.refreshCanvas()
+  }
 
   // Oh no, what are you doing, step palette~
   function stepPalette(step: number, primary: boolean) {
@@ -189,7 +206,15 @@
   </menu>
   <section class='content'>
     <section class='left'>
-      <PaletteSection refresh={refreshPalette} bind:primaryColorIndex bind:secondaryColorIndex file={focusedFile} on:select={handlePaletteSelect} />
+      <Dropdown
+        size="sm"
+        bind:selectedId={selectedPaletteID}
+        items={[
+          { id: 0, text: "<image>"},
+          { id: 1, text: "test palette"},
+        ]}
+      />
+      <PaletteSection refresh={refreshPalette} bind:primaryColorIndex bind:secondaryColorIndex file={focusedFile} fakePalette={fakePalette} on:select={handlePaletteSelect} />
       <article>
         <ColorSelector bind:red bind:green bind:blue bind:alpha />
         <ColorIndex bind:red bind:green bind:blue bind:alpha index={primaryColorIndex} file={focusedFile} on:refresh={()=>refreshPalette={}} />
@@ -302,7 +327,7 @@
   }
   .left {
     display: grid;
-    grid-template-rows: minmax(0, 1fr) auto;
+    grid-template-rows: auto minmax(0, 1fr) auto;
   }
   .toolbar {
     display: flex;

frontend/src/sections/Palette.svelte

@@ -35,6 +35,16 @@
       lastFile = file
     }
   }
+
+  export let fakePalette: Uint32Array | undefined
+  let palette: Uint32Array | undefined[]
+  $: {
+    if (fakePalette) {
+      palette = fakePalette
+    } else {
+      palette = file ? file.canvas.palette : []
+    }
+  }
   
   function paletteClick(event: MouseEvent) {
     const target = event.target as HTMLSpanElement
@@ -48,16 +58,15 @@
     }
   }
   function handleWheel(event: WheelEvent) {
-    if (!file) return
     if (event.deltaX < 0) {
-      secondaryColorIndex = (secondaryColorIndex - 1 + file.canvas.palette.length) % file.canvas.palette.length
+      secondaryColorIndex = (secondaryColorIndex - 1 + palette.length) % palette.length
     } else if (event.deltaX > 0) {
-      secondaryColorIndex = (secondaryColorIndex + 1) % file.canvas.palette.length
+      secondaryColorIndex = (secondaryColorIndex + 1) % palette.length
     }
     if (event.deltaY < 0) {
-      primaryColorIndex = (primaryColorIndex - 1 + file.canvas.palette.length) % file.canvas.palette.length
+      primaryColorIndex = (primaryColorIndex - 1 + palette.length) % palette.length
     } else if (event.deltaY > 0) {
-      primaryColorIndex = (primaryColorIndex + 1) % file.canvas.palette.length
+      primaryColorIndex = (primaryColorIndex + 1) % palette.length
     }
   }
 
@@ -118,24 +127,22 @@
 </script>
 
 <main on:wheel={handleWheel}>
-  {#if file}
-    {#each file.canvas.palette as palette, paletteIndex}
-      {#if draggingIndex !== -1 && (paletteIndex === hoveringIndex || (paletteIndex === hoveringIndex-1 && paletteIndex === file.canvas.palette.length-2))}
-        <span class="entry primary">
-          <span class="checkerboard"></span>
-          <span style="background-color: rgba({file.canvas.palette[draggingIndex]&0xFF},{(file.canvas.palette[draggingIndex]>>8)&0xFF},{(file.canvas.palette[draggingIndex]>>16)&0xFF},{((file.canvas.palette[draggingIndex]>>24)&0xFF)/255})" class="color"></span>
-          <span class='label'>{draggingIndex}</span>
-        </span>
-      {/if}
-      {#if paletteIndex !== draggingIndex}
-        <span on:click={paletteClick} x-index={paletteIndex} class='entry{paletteIndex===primaryColorIndex?' primary':''}{paletteIndex===secondaryColorIndex?' secondary':''}{paletteIndex===draggingIndex?' hide':''}' use:swatchDrag>
-          <span class="checkerboard"></span>
-          <span style="background-color: rgba({palette&0xFF},{(palette>>8)&0xFF},{(palette>>16)&0xFF},{((palette>>24)&0xFF)/255})" class="color"></span>
-          <span class='label'>{paletteIndex}</span>
-        </span>
-      {/if}
-    {/each}
-  {/if}
+  {#each palette as swatch, swatchIndex}
+    {#if draggingIndex !== -1 && (swatchIndex === hoveringIndex || (swatchIndex === hoveringIndex-1 && swatchIndex === palette.length-1))}
+      <span class="entry primary">
+        <span class="checkerboard"></span>
+        <span style="background-color: rgba({palette[draggingIndex]&0xFF},{(palette[draggingIndex]>>8)&0xFF},{(palette[draggingIndex]>>16)&0xFF},{((palette[draggingIndex]>>24)&0xFF)/255})" class="color"></span>
+        <span class='label'>{draggingIndex}</span>
+      </span>
+    {/if}
+    {#if swatchIndex !== draggingIndex}
+      <span on:click={paletteClick} x-index={swatchIndex} class='entry{swatchIndex===primaryColorIndex?' primary':''}{swatchIndex===secondaryColorIndex?' secondary':''}{swatchIndex===draggingIndex?' hide':''}' use:swatchDrag>
+        <span class="checkerboard"></span>
+        <span style="background-color: rgba({swatch&0xFF},{(swatch>>8)&0xFF},{(swatch>>16)&0xFF},{((swatch>>24)&0xFF)/255})" class="color"></span>
+        <span class='label'>{swatchIndex}</span>
+      </span>
+    {/if}
+  {/each}
 </main>
 
 <style>

frontend/src/types/canvas.ts

@@ -4,6 +4,7 @@ export class Canvas {
   width: number
   height: number
   palette: Uint32Array // 32-bit RGBA palette
+  fakePalette: Uint32Array // 32-bit RGBA palette
   pixels: Uint8Array // 8-bit indices into the palette
   public isIndexed: boolean = false
   canvas: HTMLCanvasElement
@@ -199,9 +200,19 @@ export class Canvas {
     }
     this.palette[to] = temp
   }
+  setFakePalette(palette: Uint32Array | undefined) {
+    this.fakePalette = palette
+  }
   refreshImageData() {
+    let palette = this.palette
+    if (this.fakePalette) {
+      palette = this.fakePalette
+    }
     for (let i = 0; i < this.pixels.length; i++) {
-      let color = this.palette[this.pixels[i]]
+      let color: number = 0
+      if (this.pixels[i] < palette.length) {
+        color = palette[this.pixels[i]]
+      }
       this.imageData.data[i * 4 + 0] = color & 0xFF
       this.imageData.data[i * 4 + 1] = (color >> 8) & 0xFF
       this.imageData.data[i * 4 + 2] = (color >> 16) & 0xFF