Factor segment processing, output raw segs JSON

rsimmons · Jan 10, 2019 · 02a9a56 · 02a9a56
1 parent 52abd14
commit 02a9a56
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Showing 2 changed files with 61 additions and 43 deletions.
diff --git a/lib/render.js b/lib/render.js
@@ -123,34 +123,7 @@ function* generateEdgesVertical(triGrid) {
   }
 }
 
-function combineSegments(segments) {
-  const result = [];
-
-  // Segment we are building but have not yet "emittted"
-  let openSeg;
-
-  function emitAnySeg() {
-    if (openSeg) {
-      result.push(openSeg);
-      openSeg = undefined;
-    }
-  }
-
-  for (const seg of segments) {
-    if (!openSeg || (seg[0].x !== openSeg[1].x) || (seg[0].y !== openSeg[1].y)) {
-      emitAnySeg();
-      openSeg = [{x: seg[0].x, y: seg[0].y}, {x: seg[1].x, y: seg[1].y}]; // clone seg
-    } else {
-      openSeg[1].x = seg[1].x;
-      openSeg[1].y = seg[1].y;
-    }
-  }
-  emitAnySeg();
-
-  return result;
-}
-
-function triGridToDumbSegments(triGrid) {
+function triGridToUncombinedIntegerSegmentGroups(triGrid) {
   const segmentsNESW = [];
   for (const {tAbove, tBelow, leftV, rightV} of generateEdgesNESW(triGrid)) {
     let draw = false;
@@ -268,18 +241,54 @@ function triGridToDumbSegments(triGrid) {
     }
   });
 
-  return [].concat(combineSegments(segmentsNESW), combineSegments(segmentsNWSE), combineSegments(segmentsVertical));
+  return {
+    nesw: segmentsNESW,
+    nwse: segmentsNWSE,
+    vertical: segmentsVertical,
+  };
+}
+
+function combineSegments(segments) {
+  const result = [];
+
+  // Segment we are building but have not yet "emittted"
+  let openSeg;
+
+  function emitAnySeg() {
+    if (openSeg) {
+      result.push(openSeg);
+      openSeg = undefined;
+    }
+  }
+
+  for (const seg of segments) {
+    if (!openSeg || (seg[0].x !== openSeg[1].x) || (seg[0].y !== openSeg[1].y)) {
+      emitAnySeg();
+      openSeg = [{x: seg[0].x, y: seg[0].y}, {x: seg[1].x, y: seg[1].y}]; // clone seg
+    } else {
+      openSeg[1].x = seg[1].x;
+      openSeg[1].y = seg[1].y;
+    }
+  }
+  emitAnySeg();
+
+  return result;
+}
+
+// Makes all triangles equilateral with side length 1
+const VERT_COORD_SCALE_X = 0.5*Math.sqrt(3);
+const VERT_COORD_SCALE_Y = 0.5;
+
+function scaleIntegerSegments(segments) {
+  return segments.map(([a, b]) => ([{x: VERT_COORD_SCALE_X*a.x, y: VERT_COORD_SCALE_Y*a.y}, {x: VERT_COORD_SCALE_X*b.x, y: VERT_COORD_SCALE_Y*b.y}]));
 }
 
-function segmentsToSVG(triGrid, segments, svgOpts) {
+function segmentGroupsToSVG(triGrid, segmentGroups, svgOpts) {
   const padFrac = (svgOpts && svgOpts.padFrac !== undefined) ? svgOpts.padFrac : 0;
   const splitPaths = (svgOpts && svgOpts.splitPaths !== undefined) ? svgOpts.splitPaths : false;
 
-  // Makes all triangles equilateral with side length 1
-  const scaleX = 0.5*Math.sqrt(3);
-  const scaleY = 0.5;
-
-  const scaledSegments = segments.map(([a, b]) => ([{x: scaleX*a.x, y: scaleY*a.y}, {x: scaleX*b.x, y: scaleY*b.y}]));
+  const combinedSegments = [].concat(combineSegments(segmentGroups.nesw), combineSegments(segmentGroups.nwse), combineSegments(segmentGroups.vertical));
+  const scaledSegments = scaleIntegerSegments(combinedSegments);
 
   const pathPieces = [];
   if (splitPaths) {
@@ -295,8 +304,8 @@ function segmentsToSVG(triGrid, segments, svgOpts) {
   }
   const pathStr = pathPieces.join('');
 
-  const unframedWidth = scaleX*triGrid.size.x;
-  const unframedHeight = scaleY*triGrid.size.y;
+  const unframedWidth = VERT_COORD_SCALE_X*triGrid.size.x;
+  const unframedHeight = VERT_COORD_SCALE_Y*triGrid.size.y;
   const frameDim = padFrac*Math.max(unframedWidth, unframedHeight);
   const viewBoxOrigX = -frameDim;
   const viewBoxOrigY = -frameDim;
@@ -306,13 +315,21 @@ function segmentsToSVG(triGrid, segments, svgOpts) {
   return `<svg viewBox="${viewBoxOrigX} ${viewBoxOrigY} ${viewBoxWidth} ${viewBoxHeight}" xmlns="http://www.w3.org/2000/svg"><g stroke="black" stroke-width="0.4" stroke-linecap="round">${pathStr}</g></svg>`;
 }
 
-function renderSceneToSVG(scene, svgOpts) {
+function segmentGroupsToFlatUncombinedScaled(segmentGroups) {
+  const flatSegments = [].concat(segmentGroups.nesw, segmentGroups.nwse, segmentGroups.vertical);
+  return scaleIntegerSegments(flatSegments);
+}
+
+function renderScene(scene, svgOpts) {
   const {triGrid, offset} = createTriGridForScene(scene);
   renderSceneToTriGrid(scene, triGrid, offset);
-  const segments = triGridToDumbSegments(triGrid);
-  return segmentsToSVG(triGrid, segments, svgOpts);
+  const segmentGroups = triGridToUncombinedIntegerSegmentGroups(triGrid);
+  return {
+    svg: segmentGroupsToSVG(triGrid, segmentGroups, svgOpts),
+    uncombinedSegments: segmentGroupsToFlatUncombinedScaled(segmentGroups),
+  };
 }
 
 module.exports = {
-  renderSceneToSVG,
+  renderScene,
 };
diff --git a/sketches/util.js b/sketches/util.js
@@ -1,15 +1,16 @@
 const fs = require('fs');
 
 const {createScene, ops} = require('../lib/scene');
-const {renderSceneToSVG} = require('../lib/render');
+const {renderScene} = require('../lib/render');
 
 function makeSketch(size, svgOpts, genFunc) {
   const scene = createScene(size);
 
   genFunc(scene, ops);
 
-  const svg = renderSceneToSVG(scene, svgOpts);
+  const {svg, uncombinedSegments} = renderScene(scene, svgOpts);
   fs.writeFileSync('out.svg', svg);
+  fs.writeFileSync('out_uncombined_segments.json', JSON.stringify(uncombinedSegments));
 }
 
 module.exports = {