WIP: place ship in final collision position

html/images/space.svg

@@ -659,11 +659,35 @@
         // console.log("ship landed", s, "edge", s.collision.edge.ya);
       if (s.collision) {
         // console.log("a");
-        s.velocity = { x: 0, y: 0 };
         const baseSlope = slope(s.collision.edge);
+        const { xa, ya, xb, yb } = s.collision.edge;
+        const baseLine = { x1: xa, y1: ya, x2: xb, y2: yb };
+
+        const velocityLine = {
+          x1: s.position.x,
+          y1: s.position.y,
+          x2: s.position.x + s.velocity.x,
+          y2: s.position.y + s.velocity.y
+        };
+
+        const baseNrmlIntxn = perpIntxn(baseSlope, xa, ya, s.position.x, s.position.y);
+        const baseVelIntxn = lineIntxnPt(baseLine, velocityLine);
+        const baseSegLength = distance(baseNrmlIntxn.x, baseNrmlIntxn.y , baseVelIntxn.x, baseVelIntxn.y);
+        const normalSegLength = distance(baseNrmlIntxn.x, baseNrmlIntxn.y, s.position.x, s.position.y);
+        const theta = Math.atan(normalSegLength / baseSegLength);
+        const h = 5 / Math.sin(theta);
+        const cl = document.createElementNS(namespaceURIsvg, 'line');
+        cl.setAttribute('x1', baseVelIntxn.x);
+        cl.setAttribute('y1', baseVelIntxn.y);
+        cl.setAttribute('x2', s.position.x);
+        cl.setAttribute('y2', s.position.y);
+        console.log("h", h);
+
+        const clPt = cl.getPointAtLength(h);
+        console.log("clPt", clPt);
+
         const normalSlope = 1 / -baseSlope;
         const radAngle = Math.atan(normalSlope);
-        const { xa, ya, xb, yb } = s.collision.edge;
         const foot = perpIntxn(baseSlope, xa, ya, xc, yc);
         const el = document.createElementNS(namespaceURIsvg, 'line');
         el.setAttribute('x1', foot.x);
@@ -683,7 +707,7 @@
         // console.log("foot", foot, "line", el, "length", el.getTotalLength());
         svg.appendChild(el);
         // console.log(el, el.getTotalLength());
-        const collPt = el.getPointAtLength(5);
+        // const collPt = el.getPointAtLength(5);
         // let l = drawLine(foot.x, foot.y, foot.x - posX, foot.y - posY);
         // let l = drawLine(foot.x, foot.y, foot.x - posY, foot.y - posX);
         // s.position = { x: foot.x - posY, y: foot.y - posX };
@@ -691,7 +715,10 @@
         // console.log("ship position", s.position);
         // console.log("line length", l.getTotalLength(), l, foot.x - posY, foot.y - posX);
 
-        s.position = { x: xc, y: yc }
+        s.velocity = { x: 0, y: 0 };
+        // s.position = { x: xc, y: yc }
+        s.position = { x: clPt.x, y: clPt.y }
+        console.log("s.position", s.position);
         s.node.style.transform = `translate(${s.position.x}px, ${s.position.y}px)`;
       } else {
         // console.log("c");
@@ -860,7 +887,7 @@
       // console.log("S POSITION", s.position);
       updateBullets(elapsed);
       // updateEdges(position);
-      updateLines(elapsed, collE, {x, y}, {x: s.position.x, y: s.position.y});
+      if (!s.collision) updateLines(elapsed, collE, {x, y}, s.position);
       if (drawCollisionLines) updateTriangles(position);
 
       // const collision = detectCollisions(position, allWallCorners, findAllEdges(allEdgePts, position), getCollisionEdges(edgeszz, position));