[T3] add polygon functions

T3/canvas.css

@@ -11,4 +11,15 @@ canvas {
   display:block; 
   height: 100%;
   width: 100%;
+}
+
+div {
+  position: absolute;
+  left: 10px;
+  top: 10px;
+  width: 300px;
+}
+
+#number {
+  width: 50px;
 }
\ No newline at end of file

T3/lines.html

@@ -8,7 +8,13 @@
     <canvas id="canvas">
       Your browser does not support the HTML5 canvas tag.
     </canvas>
-    <p>asdsadsa</p>
+    <div>
+      <h3> Gerador de Polígonos </h3>
+      Informe um número de 3 a 8:
+      <input type="number" id="number" step="1" min="3" max="8" value="3" required/>
+      <input type="submit" onclick="generatePolygon()" value="Gerar"/>
+      <span class="validity"></span>
+    </div>
   </body>
 
   <script type="text/javascript" src="lines.js"></script>

T3/lines.js

@@ -155,6 +155,66 @@ function handleMouse() {
   } 
 }
 
+function generatePolygon() {
+  edges = parseInt(document.getElementById("number").value,10);
+  if (edges >= 3 && edges <= 8) {
+    lines = [];
+    switch (edges) {
+      case 3:
+        lines = [new Line(centerX,centerY-300,centerX+300,centerY+300), //linha \
+                 new Line(centerX,centerY-300,centerX-300,centerY+300), //linha /
+                 new Line(centerX-300,centerY+300,centerX+300,centerY+300)]; //linha _
+        break;
+      case 4:
+        lines = [new Line(centerX-300,200,centerX+300,200), //linha _ topo
+                 new Line(centerX+300,200,centerX+300,800), //linha | direita
+                 new Line(centerX-300,200,centerX-300,800), //linha | esquerda
+                 new Line(centerX-300,800,centerX+300,800)]; //linha _ baixo
+        break;
+      case 5:
+        lines = [new Line(centerX,centerY-350,centerX+300,centerY-150), //linha \ direita 
+                 new Line(centerX,centerY-350,centerX-300,centerY-150), //linha / esquerda 
+                 new Line(centerX+300,centerY-150,centerX+215,centerY+200), //linha \ esquerda
+                 new Line(centerX-300,centerY-150,centerX-215,centerY+200), //linha / direita
+                 new Line(centerX-215,centerY+200,centerX+215,centerY+200)]; //linha _ baixo
+        break;
+      case 6:
+        lines = [new Line(centerX-200,200,centerX+200,200), //linha _ topo
+                 new Line(centerX-200,200,centerX-400,550), //linha / esq
+                 new Line(centerX-400,550,centerX-200,900), //linha \ esq
+                 new Line(centerX+200,200,centerX+400,550), //linha / dir
+                 new Line(centerX+400,550,centerX+200,900), //linha \ dir
+                 new Line(centerX-200,900,centerX+200,900)]; //linha _ baixo
+        break;
+      case 7:
+        lines = [new Line(centerX-250,300,centerX,200), //linha / topo
+                 new Line(centerX,200,centerX+250,300), //linha / topo
+                 new Line(centerX-250,300,centerX-350,630), //linha / esq
+                 new Line(centerX+250,300,centerX+350,630), //linha \ dir
+                 new Line(centerX-350,630,centerX-170,900), //linha \ esq
+                 new Line(centerX+350,630,centerX+170,900), //linha / dir
+                 new Line(centerX-170,900,centerX+170,900)]; //linha _ baixo
+        break;
+      case 8:
+        lines = [new Line(centerX-220,100,centerX+220,100), //linha _ topo
+                 new Line(centerX-220,100,centerX-420,375), //linha / esq
+                 new Line(centerX-420,375,centerX-420,650), //linha | esq
+                 new Line(centerX-420,650,centerX-220,925), //linha \ esq
+                 new Line(centerX+220,100,centerX+420,375), //linha / esq
+                 new Line(centerX+420,375,centerX+420,650), //linha | esq
+                 new Line(centerX+420,650,centerX+220,925), //linha \ esq
+                 new Line(centerX-220,925,centerX+220,925)]; //linha _ baixo
+        break;
+      default:
+        break;
+    }
+    drawCurrentCanvas();
+  } else {
+    console.log("Valor inválido.");
+    alert("Valor inválido! O número de arestas deve estar no intervalo de [3..8].")
+  }
+}
+
 //function that updates screen
 function drawCurrentCanvas() {
   drawLines();