Adding instructions, ESC and Ctrl-Z functionality and some bug fixes.

README.md

@@ -78,7 +78,10 @@ To use PolygonZone, open up the [PolygonZone web application](https://roboflow.g
 4. Continue to draw as many polygons as you need.
 5. Copy the NumPy array or JSON object that contains the coordinates of the polygons you have drawn.
 
-You can zoom in and out of an image using the mouse wheel or a laptop track pad.
+## Functionalities
+- You can zoom in and out of an image using the mouse wheel or a laptop track pad.
+- You can undo the last point pressing Ctrl/Cmd+Z
+- You can discard the last unsaved polygon pressing Esc
 
 ## Contributing 🤝
 

index.html

@@ -38,14 +38,35 @@ <h1>Draw points to create polygon coordinates</h1>
                     </div>
                 </div>
                 <div class="right">
+                    <div class="how-to">
+                        <h2>How to use</h2>
+                        <ol class="ta-left">
+                            <li>Drop an image to the indicated area</li>
+                            <li>Select the desired mode: Press <kbd>L</kbd> to draw a line, or <kbd>P</kbd> to draw a polygon</li>
+                            <li>Start creating your polygon, clicking in the desired points of the image</li>
+                            <li>If in polygon mode, press <kbd>ENTER</kbd> to finish the polygon</li>
+                            <li>Repeat steps 2 - 4 as many times as you want</li>
+                            <li>To finish, copy the numpy points to your clipboard</li>
+                        </ol>
+                    </div>
+                    <div class="shortcuts">
+                        <h2>Keyboard shortcuts</h2>
+                        <ul class="ta-left">
+                            <li><kbd>L</kbd>: Switch to line drawing mode</li>
+                            <li><kbd>P</kbd>: Swicth to polygon drawing mode</li>
+                            <li><kbd>Enter</kbd>: If you drawing a polygon, end the polygon</li>
+                            <li><kbd>Esc</kbd>: When drawing, clear the current polygon</li>
+                            <li><kbd>Ctrl(Cmd)-Z</kbd>: Undo the last point</li>
+                        </ul>
+                    </div>
                     <h2>NumPy Points</h2>
                     <p>Copy the points below into your Python code.</p>
                     <a href="" id="clipboard" class="widgetButton">Copy Python to Clipboard</a>
                     <pre id="python">
                         <code>
                         </code>
                     </pre>
-                    <div class="show_normalized" style="margin-bottom: 25px;">
+                    <div class="show_normalized mb-3">
                         <label for="normalize_checkbox">Show Normalized Points from 0-1</label>
                         <input type="checkbox" id="normalize_checkbox" name="normalize_checkbox" value="normalize_checkbox">
                     </div>

script.js

@@ -91,6 +91,50 @@ function getScaledCoords(e) {
     return [x / scaleFactor, y / scaleFactor];
 }
 
+function drawCurrentPolygon (cursorX, cursorY) {
+    //ctx.clearRect(0, 0, canvas.width, canvas.height);
+    ctx.drawImage(img, 0, 0);
+    for (var i = 0; i < points.length - 1; i++) {
+        // draw arc around each point
+        ctx.beginPath();
+        ctx.strokeStyle = rgb_color;
+        ctx.arc(points[i][0], points[i][1], 5, 0, 2 * Math.PI);
+        // fill with white
+        ctx.fillStyle = 'white';
+        ctx.fill();
+        ctx.stroke();
+        drawLine(points[i][0], points[i][1], points[i + 1][0], points[i + 1][1]);
+    }
+
+    if ((points.length > 0 && drawMode == "polygon") || (points.length > 0 && points.length < 2 && drawMode == "line")) {
+        ctx.beginPath();
+        ctx.strokeStyle = rgb_color;
+        ctx.arc(points[i][0], points[i][1], 5, 0, 2 * Math.PI);
+        // fill with white
+        ctx.fillStyle = 'white';
+        ctx.fill();
+        ctx.stroke();
+
+        if (cursorX && cursorY) {
+            drawLine(points[points.length - 1][0], points[points.length - 1][1], cursorX, cursorY);
+        }
+
+        if (points.length == 2 && drawMode == "line") {
+            console.log("line");
+            // draw arc around each point
+            ctx.beginPath();
+            ctx.strokeStyle = rgb_color;
+            ctx.arc(points[0][0], points[0][1], 5, 0, 2 * Math.PI);
+            // fill with white
+            ctx.fillStyle = 'white';
+            ctx.fill();
+            ctx.stroke();
+            masterPoints.push(points);
+            points = [];
+        }
+    }
+}
+
 function drawAllPolygons () {
     // draw all points for previous regions
     for (var i = 0; i < masterPoints.length; i++) {
@@ -124,6 +168,15 @@ function drawAllPolygons () {
     }
 }
 
+function getParentPoints () {
+    var parentPoints = [];
+    for (var i = 0; i < masterPoints.length; i++) {
+        parentPoints.push(masterPoints[i]);
+    }
+    parentPoints.push(points);
+    return parentPoints;
+}
+
 function clearall() {
     ctx.clearRect(0, 0, canvas.width, canvas.height);
     ctx.drawImage(img, 0, 0);
@@ -180,83 +233,25 @@ canvas.addEventListener('mousemove', function(e) {
     ycoord.innerHTML = y;
 
     if (canvas.style.cursor == 'crosshair') {
-        //ctx.clearRect(0, 0, canvas.width, canvas.height);
-        ctx.drawImage(img, 0, 0);
-        for (var i = 0; i < points.length - 1; i++) {
-            // draw arc around each point
-            ctx.beginPath();
-            ctx.strokeStyle = rgb_color;
-            ctx.arc(points[i][0], points[i][1], 5, 0, 2 * Math.PI);
-            // fill with white
-            ctx.fillStyle = 'white';
-            ctx.fill();
-            ctx.stroke();
-            drawLine(points[i][0], points[i][1], points[i + 1][0], points[i + 1][1]);
-        }
-        if ((points.length > 0 && drawMode == "polygon") || (points.length > 0 && points.length < 2 && drawMode == "line")) {
-            ctx.beginPath();
-            ctx.strokeStyle = rgb_color;
-            ctx.arc(points[i][0], points[i][1], 5, 0, 2 * Math.PI);
-            // fill with white
-            ctx.fillStyle = 'white';
-            ctx.fill();
-            ctx.stroke();
-            drawLine(points[points.length - 1][0], points[points.length - 1][1], x, y);
-
-            if (points.length == 2 && drawMode == "line") {
-                console.log("line");
-                // draw arc around each point
-                ctx.beginPath();
-                ctx.strokeStyle = rgb_color;
-                ctx.arc(points[0][0], points[0][1], 5, 0, 2 * Math.PI);
-                // fill with white
-                ctx.fillStyle = 'white';
-                ctx.fill();
-                ctx.stroke();
-                masterPoints.push(points);
-                points = [];
-            }
-        }
-        var parentPoints = [];
-
-        for (var i = 0; i < masterPoints.length; i++) {
-            parentPoints.push(masterPoints[i]);
-        }
-        parentPoints.push(points);
-
+        drawCurrentPolygon(x, y)
         drawAllPolygons();
     }
 });
 
+
+
 window.addEventListener('keydown', function(e) {
+    e.stopImmediatePropagation()
+    let validKey = false
+
     if (e.key === 'Enter') {
+        validKey = true
         canvas.style.cursor = 'default';
-        // remove line drawn by mouseover
-        // ctx.clearRect(0, 0, canvas.width, canvas.height);
-        // join the dots
-        drawLine(points[0][0], points[0][1], points[points.length - 1][0], points[points.length - 1][1]);
-        // fill polygon with color
-        if (drawMode == 'polygon') {
-            ctx.beginPath();
-            ctx.moveTo(points[0][0], points[0][1]);
-            ctx.fillStyle = opaque_color;
-            for (var i = 1; i < points.length; i++) {
-                ctx.lineTo(points[i][0], points[i][1]);
-            }
-            ctx.closePath();
-            ctx.fill();
-            // draw line connecting last two points
-        }
+
+        // save current polygon points
         masterPoints.push(points);
-        // draw arc around last point
-        ctx.beginPath();
-        ctx.strokeStyle = rgb_color;
-        ctx.arc(points[points.length - 1][0], points[points.length - 1][1], 5, 0, 2 * Math.PI);
-        // fill with white
-        ctx.fillStyle = 'white';
-        ctx.fill();
-        ctx.stroke();
         points = [];
+
         // dont choose a color that has already been chosen
         var remaining_choices = color_choices.filter(function(x) {
             return !masterColors.includes(x);
@@ -267,9 +262,25 @@ window.addEventListener('keydown', function(e) {
         }
 
         rgb_color = remaining_choices[Math.floor(Math.random() * remaining_choices.length)];
-
         masterColors.push(rgb_color);
     }
+
+    if (e.key === 'Escape') {
+        validKey = true
+        points = []
+    }
+
+    if (e.key === 'z' && (e.ctrlKey || e.metaKey)) {
+        validKey = true
+        points.pop()
+    }
+
+    if (validKey) {
+        drawCurrentPolygon()
+        drawAllPolygons();
+        var parentPoints = getParentPoints();
+        writePoints(parentPoints);
+    }
 });
 
 canvas.addEventListener('drop', function(e) {
@@ -327,6 +338,15 @@ function writePoints(parentPoints) {
         parentPoints = normalized;
     }
 
+    // clean empty points
+    parentPoints = parentPoints.filter(points => !!points.length);
+
+    if (!parentPoints.length) {
+        document.querySelector('#python').innerHTML = '';
+        document.querySelector('#json').innerHTML;
+        return;
+    }
+
     // create np.array list
     var code_template = `
 [
@@ -339,6 +359,7 @@ ${points.map(function(point) {
 }).join(',')}
 ]
     `;
+
     document.querySelector('#python').innerHTML = code_template;
 
     var json_template = `
@@ -378,28 +399,13 @@ canvas.addEventListener('click', function(e) {
     }
 
     ctx.arc(x, y, 155, 0, 2 * Math.PI);
-    // concat all points into one array
-    var parentPoints = [];
-
-    for (var i = 0; i < masterPoints.length; i++) {
-        parentPoints.push(masterPoints[i]);
-    }
-    // add "points"
-    parentPoints.push(points);
 
+    var parentPoints = getParentPoints();
     writePoints(parentPoints);
 });
 
 document.querySelector('#normalize_checkbox').addEventListener('change', function(e) {
     showNormalized = e.target.checked;
-    // normalize all
-    var parentPoints = [];
-
-    for (var i = 0; i < masterPoints.length; i++) {
-        parentPoints.push(masterPoints[i]);
-    }
-
-    parentPoints.push(points);
-
+    var parentPoints = getParentPoints();
     writePoints(parentPoints);
 });

styles.css

@@ -167,3 +167,24 @@ pre {
 footer {
     margin-top: 20px;
 }
+
+li {
+    margin-bottom: 4px;
+}
+
+/* Helpers */
+.ta-left {
+    text-align: left;
+}
+
+.mb-1 {
+    margin-bottom: 8px;
+}
+
+.mb-2 {
+    margin-bottom: 16px;
+}
+
+.mb-3 {
+    margin-bottom: 24px;
+}