driving base sim

sim/visuals/robotgametable.ts

@@ -0,0 +1,55 @@
+namespace pxsim {
+    export class RobotGameTable {
+        readonly ctx: CanvasRenderingContext2D;
+        readonly data: ImageData;
+
+        cx: number; // cm
+        cy: number; // cm
+        angle: number; // radians
+        cwidth: number; // cm
+
+        constructor(public canvas: HTMLCanvasElement, public scale: number) {
+            this.ctx = this.canvas.getContext("2d");
+            this.data = this.ctx.getImageData(0, 0, this.canvas.width, this.canvas.height);
+            this.cx = this.width / 2;
+            this.cy = 0;
+        }
+
+        /**
+         * Gets the width in cm
+         */
+        get width() { 
+            return this.canvas.width * this.scale;
+        }
+
+        /**
+         * gets the height in cm
+         */
+        get height() {
+            return this.canvas.height * this.scale;
+        }
+
+        color(): number {
+            // compute color sensor position from center;
+            // todo
+            const px = Math.max(0, Math.min(this.data.width, (this.cx ) / this.scale));
+            const py = Math.max(0, Math.min(this.data.height, (this.cy ) / this.scale));
+            // get color
+            const i = px * this.data.width + py;
+            let c = 
+                (this.data.data[i] << 16) | (this.data.data[i + 1] << 8) | (this.data.data[i + 2]);
+            // map color to known color
+            return c;
+        }
+
+        intensity(): number {
+            const c = this.color();
+            return ((c >> 16 & 0xff) + (c >> 8 & 0xff) + (c & 0xff)) / 3;
+        }
+
+        ultrasonicDistance() {
+            // obstacles?
+            
+        }
+    }
+}