Smarter transforms collapsing. Fixes #208

plugins/convertTransform.js

@@ -80,8 +80,13 @@ function convertTransform(item, attrName, params) {
 
     if (
         params.collapseIntoOne &&
-        (data.length >= 3 ||
-         data.some(function(i) { return i.name === 'matrix'; })
+        (
+            data.length >= 3 ||
+            data.length == 2 &&
+            (
+                data[0].name === 'matrix' || data[1].name === 'matrix' ||
+                data[0].name == data[1].name
+            )
         )
     ) {
         data = [transformsMultiply(data, params)];
@@ -89,6 +94,10 @@ function convertTransform(item, attrName, params) {
         if (params.matrixToTransform) {
             data = [matrixToTransform(data[0], params)];
         }
+
+        if (params.removeUseless) {
+            data = removeUseless(data);
+        }
     }
 
     item.attr(attrName).value = js2transform(data, params);
@@ -192,8 +201,11 @@ function removeUseless(transforms) {
         // translate(0), rotate(0), skewX(0), skewY(0)
         if (
             ['translate', 'rotate', 'skewX', 'skewY'].indexOf(transform.name) > -1 &&
-            transform.data.length === 1 &&
-            transform.data[0] === 0
+            (transform.data.length === 1 || transform.name === 'rotate') &&
+            transform.data[0] === 0 ||
+            transform.name === 'translate' &&
+            transform.data[0] === 0 &&
+            transform.data[1] === 0
         ) {
             return false;
         // scale(1)

test/plugins/convertTransform.04.svg

@@ -1,16 +1,20 @@
 <svg xmlns="http://www.w3.org/2000/svg">
     <g transform="translate(0)"/>
+    <g transform="translate(0 0)"/>
     <g transform="translate(0 50)"/>
     <g transform="scale(1)"/>
     <g transform="scale(1 2)"/>
     <g transform="rotate(0)"/>
+    <g transform="rotate(0 100 100)"/>
     <g transform="skewX(0)"/>
     <g transform="skewY(0)"/>
+    <g transform="translate(0,-100) translate(0,100)"/>
 </svg>
 
 @@@
 
 <svg xmlns="http://www.w3.org/2000/svg">
+    <g transform=""/>
     <g transform=""/>
     <g transform="translate(0 50)"/>
     <g transform=""/>
@@ -18,4 +22,6 @@
     <g transform=""/>
     <g transform=""/>
     <g transform=""/>
+    <g transform=""/>
+    <g transform=""/>
 </svg>