Merge pull request #717 from jonobr1/issue-716-baseline

Improve Text.baseline consistency across all renderers

build/two.js

@@ -737,8 +737,8 @@ var Two = (() => {
       svg: "SVGRenderer",
       canvas: "CanvasRenderer"
     },
-    Version: "v0.8.12",
-    PublishDate: "2023-10-16T17:55:26.551Z",
+    Version: "v0.8.13",
+    PublishDate: "2024-02-20T20:04:05.976Z",
     Identifier: "two-",
     Resolution: 12,
     AutoCalculateImportedMatrices: true,
@@ -2341,6 +2341,12 @@ var Two = (() => {
       middle: "center",
       right: "end"
     },
+    baselines: {
+      top: "top",
+      middle: "middle",
+      bottom: "bottom",
+      baseline: "alphabetic"
+    },
     shim: function(elem, name) {
       elem.tagName = elem.nodeName = name || "canvas";
       elem.nodeType = 1;
@@ -2725,7 +2731,7 @@ var Two = (() => {
         const isOffset = fill._renderer && fill._renderer.offset && stroke._renderer && stroke._renderer.offset;
         const dashes = this.dashes;
         const alignment = canvas.alignments[this._alignment] || this._alignment;
-        const baseline = this._baseline;
+        const baseline = canvas.baselines[this._baseline] || this._baseline;
         let a, b, c, d, e, sx, sy, x1, y1, x2, y2;
         if (!defaultMatrix) {
           ctx.save();
@@ -2828,8 +2834,8 @@ var Two = (() => {
           let scalar = 1;
           switch (decoration) {
             case "underline":
-              y1 = metrics.actualBoundingBoxAscent;
-              y2 = metrics.actualBoundingBoxAscent;
+              y1 = metrics.actualBoundingBoxDescent;
+              y2 = metrics.actualBoundingBoxDescent;
               break;
             case "strikethrough":
               y1 = 0;
@@ -8142,6 +8148,12 @@ var Two = (() => {
       center: "middle",
       right: "end"
     },
+    baselines: {
+      top: "hanging",
+      middle: "middle",
+      bottom: "ideographic",
+      baseline: "alphabetic"
+    },
     createElement: function(name, attrs) {
       const tag = name;
       const elem = document.createElementNS(svg.ns, tag);
@@ -8584,7 +8596,7 @@ var Two = (() => {
           changed["text-anchor"] = svg.alignments[this._alignment] || this._alignment;
         }
         if (this._flagBaseline) {
-          changed["alignment-baseline"] = changed["dominant-baseline"] = this._baseline;
+          changed["dominant-baseline"] = svg.baselines[this._baseline] || this._baseline;
         }
         if (this._flagStyle) {
           changed["font-style"] = this._style;
@@ -9731,8 +9743,8 @@ var Two = (() => {
           const metrics = ctx.measureText(elem.value);
           switch (decoration) {
             case "underline":
-              y1 = metrics.actualBoundingBoxAscent;
-              y2 = metrics.actualBoundingBoxAscent;
+              y1 = metrics.actualBoundingBoxDescent;
+              y2 = metrics.actualBoundingBoxDescent;
               break;
             case "strikethrough":
               y1 = 0;
@@ -9754,9 +9766,10 @@ var Two = (() => {
         const ctx = webgl.ctx;
         ctx.font = [elem._style, elem._weight, elem._size + "px/" + elem._leading + "px", elem._family].join(" ");
         ctx.textAlign = "center";
-        ctx.textBaseline = elem._baseline;
-        let width = ctx.measureText(elem._value).width * 1.25;
-        let height = Math.max(elem._size, elem._leading) * 1.25;
+        ctx.textBaseline = Renderer.Utils.baselines[elem._baseline] || elem._baseline;
+        const metrics = ctx.measureText(elem._value);
+        let width = metrics.width;
+        let height = 1.15 * (metrics.actualBoundingBoxAscent + metrics.actualBoundingBoxDescent);
         if (this._linewidth && !webgl.isHidden.test(this._stroke)) {
           width += this._linewidth * 2;
           height += this._linewidth * 2;
@@ -9785,6 +9798,10 @@ var Two = (() => {
             rect.top = 0;
             rect.bottom = height;
             break;
+          case "baseline":
+            rect.top = -h * 1.5;
+            rect.bottom = h * 0.5;
+            break;
           default:
             rect.top = -h;
             rect.bottom = h;

build/two.module.js

@@ -718,8 +718,8 @@ var Constants = {
     svg: "SVGRenderer",
     canvas: "CanvasRenderer"
   },
-  Version: "v0.8.12",
-  PublishDate: "2023-10-16T17:55:26.551Z",
+  Version: "v0.8.13",
+  PublishDate: "2024-02-20T20:04:05.976Z",
   Identifier: "two-",
   Resolution: 12,
   AutoCalculateImportedMatrices: true,
@@ -2322,6 +2322,12 @@ var canvas = {
     middle: "center",
     right: "end"
   },
+  baselines: {
+    top: "top",
+    middle: "middle",
+    bottom: "bottom",
+    baseline: "alphabetic"
+  },
   shim: function(elem, name) {
     elem.tagName = elem.nodeName = name || "canvas";
     elem.nodeType = 1;
@@ -2706,7 +2712,7 @@ var canvas = {
       const isOffset = fill._renderer && fill._renderer.offset && stroke._renderer && stroke._renderer.offset;
       const dashes = this.dashes;
       const alignment = canvas.alignments[this._alignment] || this._alignment;
-      const baseline = this._baseline;
+      const baseline = canvas.baselines[this._baseline] || this._baseline;
       let a, b, c, d, e, sx, sy, x1, y1, x2, y2;
       if (!defaultMatrix) {
         ctx.save();
@@ -2809,8 +2815,8 @@ var canvas = {
         let scalar = 1;
         switch (decoration) {
           case "underline":
-            y1 = metrics.actualBoundingBoxAscent;
-            y2 = metrics.actualBoundingBoxAscent;
+            y1 = metrics.actualBoundingBoxDescent;
+            y2 = metrics.actualBoundingBoxDescent;
             break;
           case "strikethrough":
             y1 = 0;
@@ -8123,6 +8129,12 @@ var svg = {
     center: "middle",
     right: "end"
   },
+  baselines: {
+    top: "hanging",
+    middle: "middle",
+    bottom: "ideographic",
+    baseline: "alphabetic"
+  },
   createElement: function(name, attrs) {
     const tag = name;
     const elem = document.createElementNS(svg.ns, tag);
@@ -8565,7 +8577,7 @@ var svg = {
         changed["text-anchor"] = svg.alignments[this._alignment] || this._alignment;
       }
       if (this._flagBaseline) {
-        changed["alignment-baseline"] = changed["dominant-baseline"] = this._baseline;
+        changed["dominant-baseline"] = svg.baselines[this._baseline] || this._baseline;
       }
       if (this._flagStyle) {
         changed["font-style"] = this._style;
@@ -9712,8 +9724,8 @@ var webgl = {
         const metrics = ctx.measureText(elem.value);
         switch (decoration) {
           case "underline":
-            y1 = metrics.actualBoundingBoxAscent;
-            y2 = metrics.actualBoundingBoxAscent;
+            y1 = metrics.actualBoundingBoxDescent;
+            y2 = metrics.actualBoundingBoxDescent;
             break;
           case "strikethrough":
             y1 = 0;
@@ -9735,9 +9747,10 @@ var webgl = {
       const ctx = webgl.ctx;
       ctx.font = [elem._style, elem._weight, elem._size + "px/" + elem._leading + "px", elem._family].join(" ");
       ctx.textAlign = "center";
-      ctx.textBaseline = elem._baseline;
-      let width = ctx.measureText(elem._value).width * 1.25;
-      let height = Math.max(elem._size, elem._leading) * 1.25;
+      ctx.textBaseline = Renderer.Utils.baselines[elem._baseline] || elem._baseline;
+      const metrics = ctx.measureText(elem._value);
+      let width = metrics.width;
+      let height = 1.15 * (metrics.actualBoundingBoxAscent + metrics.actualBoundingBoxDescent);
       if (this._linewidth && !webgl.isHidden.test(this._stroke)) {
         width += this._linewidth * 2;
         height += this._linewidth * 2;
@@ -9766,6 +9779,10 @@ var webgl = {
           rect.top = 0;
           rect.bottom = height;
           break;
+        case "baseline":
+          rect.top = -h * 1.5;
+          rect.bottom = h * 0.5;
+          break;
         default:
           rect.top = -h;
           rect.bottom = h;

src/renderers/canvas.js

@@ -29,6 +29,13 @@ const canvas = {
     right: 'end'
   },
 
+  baselines: {
+    top: 'top',
+    middle: 'middle',
+    bottom: 'bottom',
+    baseline: 'alphabetic'
+  },
+
   shim: function(elem, name) {
     elem.tagName = elem.nodeName = name || 'canvas';
     elem.nodeType = 1;
@@ -515,7 +522,7 @@ const canvas = {
         && stroke._renderer && stroke._renderer.offset;
       const dashes = this.dashes;
       const alignment = canvas.alignments[this._alignment] || this._alignment;
-      const baseline = this._baseline;
+      const baseline = canvas.baselines[this._baseline] || this._baseline;
 
       let a, b, c, d, e, sx, sy, x1, y1, x2, y2;
 
@@ -638,8 +645,8 @@ const canvas = {
 
         switch (decoration) {
           case 'underline':
-            y1 = metrics.actualBoundingBoxAscent;
-            y2 = metrics.actualBoundingBoxAscent;
+            y1 = metrics.actualBoundingBoxDescent;
+            y2 = metrics.actualBoundingBoxDescent;
             break;
           case 'strikethrough':
             y1 = 0;

src/renderers/svg.js

@@ -19,6 +19,13 @@ const svg = {
     right: 'end'
   },
 
+  baselines: {
+    top: 'hanging',
+    middle: 'middle',
+    bottom: 'ideographic',
+    baseline: 'alphabetic'
+  },
+
   // Create an svg namespaced element.
   createElement: function(name, attrs) {
     const tag = name;
@@ -684,7 +691,7 @@ const svg = {
         changed['text-anchor'] = svg.alignments[this._alignment] || this._alignment;
       }
       if (this._flagBaseline) {
-        changed['alignment-baseline'] = changed['dominant-baseline'] = this._baseline;
+        changed['dominant-baseline'] = svg.baselines[this._baseline] || this._baseline;
       }
       if (this._flagStyle) {
         changed['font-style'] = this._style;

src/renderers/webgl.js

@@ -999,8 +999,8 @@ const webgl = {
 
         switch (decoration) {
           case 'underline':
-            y1 = metrics.actualBoundingBoxAscent;
-            y2 = metrics.actualBoundingBoxAscent;
+            y1 = metrics.actualBoundingBoxDescent;
+            y2 = metrics.actualBoundingBoxDescent;
             break;
           case 'strikethrough':
             y1 = 0;
@@ -1033,11 +1033,13 @@ const webgl = {
         elem._leading + 'px', elem._family].join(' ');
 
       ctx.textAlign = 'center';
-      ctx.textBaseline = elem._baseline;
+      ctx.textBaseline = CanvasRenderer.Utils.baselines[elem._baseline] || elem._baseline;
 
-      // TODO: Estimate this better
-      let width = ctx.measureText(elem._value).width * 1.25;
-      let height = Math.max(elem._size, elem._leading) * 1.25;
+      const metrics = ctx.measureText(elem._value);
+      let width = metrics.width;
+      // TODO: Why does the height need to be scaled by 15%
+      // in order to not cut off / mask the bitmap data.
+      let height = 1.15 * (metrics.actualBoundingBoxAscent + metrics.actualBoundingBoxDescent);
 
       if (this._linewidth && !webgl.isHidden.test(this._stroke)) {
         width += this._linewidth * 2;
@@ -1072,6 +1074,10 @@ const webgl = {
           rect.top = 0;
           rect.bottom = height;
           break;
+        case 'baseline':
+          rect.top = - h * 1.5; // TODO: Improve calculation based on text metrics
+          rect.bottom = h * 0.5;
+          break;
         default:
           rect.top = - h;
           rect.bottom = h;

tests/suite/svg.js

@@ -406,7 +406,7 @@
 
   QUnit.test('Two.makeText', function(assert) {
 
-    assert.expect(17);
+    assert.expect(16);
 
     var two = new Two({
       width: 400,
@@ -430,7 +430,6 @@
     assert.equal(elem.getAttribute('line-height'), '17', 'The line-height attribute applied properly');
     assert.equal(elem.getAttribute('text-anchor'), 'middle', 'The text-anchor attribute applied properly.');
     assert.equal(elem.getAttribute('dominant-baseline'), 'middle', 'The dominant-baseline attribute applied properly.');
-    assert.equal(elem.getAttribute('alignment-baseline'), 'middle', 'The alignment-baseline attribute applied properly.');
     assert.equal(elem.getAttribute('font-style'), 'normal', 'The font-style attribute applied properly.');
     assert.equal(elem.getAttribute('font-weight'), '500', 'The font-weight attribute applied properly.');
     assert.equal(elem.getAttribute('text-decoration'), 'none', 'The text-decoration attribute applied properly.');

wiki/changelog/README.md

@@ -13,18 +13,20 @@ All notable changes to this project will be documented in this file. The format
 
 ## Nightly
 
++ Improved consistency of `Two.Text.baseline` rendering across all renderers
+
 ## October 16, 2023 v0.8.12
 
 <h3 class="visible">October 16, 2023</h3><version-link v="v0.8.12" />
 
-+ Added "no-referrer" policy to image requests
++ Added `"no-referrer"` policy to image requests
 + Updated extras to be compatible with `Two.Matrix` API changes
-+ Two.Path.noFill() yields `"none"` instead of `"transparent"`
-+ Two.Path.noStroke() yields `"none"` instead of `"transparent"`
-+ Two.Text.noFill() yields `"none"` instead of `"transparent"`
-+ Two.Text.noStroke() yields `"none"` instead of `"transparent"`
-+ Two.Points.noFill() yields `"none"` instead of `"transparent"`
-+ Two.Points.noStroke() yields `"none"` instead of `"transparent"`
++ `Two.Path.noFill()` yields `"none"` instead of `"transparent"`
++ `Two.Path.noStroke()` yields `"none"` instead of `"transparent"`
++ `Two.Text.noFill()` yields `"none"` instead of `"transparent"`
++ `Two.Text.noStroke()` yields `"none"` instead of `"transparent"`
++ `Two.Points.noFill()` yields `"none"` instead of `"transparent"`
++ `Two.Points.noStroke()` yields `"none"` instead of `"transparent"`
 
 ## August 7, 2023 v0.8.11