fixes

src/App.vue

@@ -1,12 +1,11 @@
 <script setup lang="ts">
 import { computed, reactive } from 'vue'
 import BlockCanvas from './components/BlockCanvas.vue'
-import { generateShape, summarize, type ShapeMode } from './composables/useShapeGenerator'
+import { generateShape, summarize } from './composables/useShapeGenerator'
 
 interface FormState {
   width: number
   height: number
-  mode: ShapeMode
   useSlabs: boolean
   useStairs: boolean
   cellSize: number
@@ -15,7 +14,6 @@ interface FormState {
 const form = reactive<FormState>({
   width: 12,
   height: 8,
-  mode: 'arch',
   useSlabs: true,
   useStairs: true,
   cellSize: 20,
@@ -35,7 +33,6 @@ const shape = computed(() => {
   return generateShape({
     width,
     height,
-    mode: form.mode,
     useSlabs: form.useSlabs,
     useStairs: form.useStairs,
   })
@@ -47,12 +44,13 @@ const stats = computed(() => summarize(shape.value))
 <template>
   <div class="page">
     <header>
-      <h1>Minecraft Arch / Ellipse Generator</h1>
+      <h1>Minecraft Arch Generator</h1>
       <p class="subtitle">
-        Enter a width and height (in blocks) for the wall panel. An arch or
-        oval opening is cut out of it, smoothed with slabs (half-block steps)
-        and stairs (beveled corners) instead of a fully jagged hole outline.
-        The result is the wall blocks you need to place, not the opening.
+        Enter a width and height (in blocks) for the wall panel. An arch
+        opening is cut out of it from the ground up, smoothed with slabs
+        (half-block steps) and stairs (beveled corners) instead of a fully
+        jagged hole outline. The result is the wall blocks you need to
+        place, not the opening.
       </p>
     </header>
 
@@ -68,14 +66,6 @@ const stats = computed(() => summarize(shape.value))
           <input type="number" v-model.number="form.height" :min="MIN_SIZE" :max="MAX_SIZE" />
         </label>
 
-        <label>
-          Opening shape
-          <select v-model="form.mode">
-            <option value="arch">Arch doorway (cut from the ground up)</option>
-            <option value="oval">Oval window (cut from the middle)</option>
-          </select>
-        </label>
-
         <label class="checkbox">
           <input type="checkbox" v-model="form.useSlabs" />
           Use slabs (half-block smoothing)

src/composables/useShapeGenerator.ts

@@ -1,5 +1,5 @@
 // Builds a Minecraft elevation-view (front-facing) block list for a wall
-// panel with an arch- or oval-shaped opening cut out of it.
+// panel with an arch-shaped opening cut out of it, grounded at the bottom.
 //
 // Each block is sub-sampled at 4 quarter-points (splitting the block into a
 // 2x2 grid) against the true ellipse boundary, so the resulting shape is
@@ -41,12 +41,9 @@ export interface Shape {
   columns: Column[]
 }
 
-export type ShapeMode = 'arch' | 'oval'
-
 export interface GenerateOptions {
   width: number
   height: number
-  mode: ShapeMode
   useSlabs: boolean
   useStairs: boolean
 }
@@ -56,9 +53,9 @@ function insideOpening(x: number, y: number, a: number, b: number): boolean {
   return (x / a) ** 2 + (y / b) ** 2 <= 1
 }
 
-/** Continuous y-coordinate of a row's center: arch shapes sit on the ground (y=0 at the bottom edge), oval shapes are centered vertically. */
-function rowCenterY(r: number, mode: ShapeMode, height: number): number {
-  return mode === 'oval' ? r - (height - 1) / 2 : r + 0.5
+/** Continuous y-coordinate of a row's center; the arch sits on the ground, so y=0 is the bottom edge of the grid. */
+function rowCenterY(r: number): number {
+  return r + 0.5
 }
 
 function classifyCell(tl: boolean, tr: boolean, bl: boolean, br: boolean, useSlabs: boolean, useStairs: boolean): Cell | null {
@@ -85,10 +82,10 @@ function classifyCell(tl: boolean, tr: boolean, bl: boolean, br: boolean, useSla
 export function generateShape(opts: GenerateOptions): Shape {
   const width = Math.max(1, Math.round(opts.width))
   const height = Math.max(1, Math.round(opts.height))
-  const { mode, useSlabs, useStairs } = opts
+  const { useSlabs, useStairs } = opts
 
   const a = width / 2
-  const b = mode === 'oval' ? height / 2 : height
+  const b = height
   const centerOffsetX = (width - 1) / 2
   const useSubSampling = useSlabs || useStairs
 
@@ -98,7 +95,7 @@ export function generateShape(opts: GenerateOptions): Shape {
     const col: Column = []
 
     for (let r = 0; r < height; r++) {
-      const cy = rowCenterY(r, mode, height)
+      const cy = rowCenterY(r)
 
       if (!useSubSampling) {
         col.push(insideOpening(cx, cy, a, b) ? null : { type: 'full' })