fixes and minor improvements

src/main.js

@@ -885,11 +885,8 @@ function updateParticle(p) {
 function applyFireDamage(dt) {
   for (let player of players) {
     if (player.dead) continue;
-    const fx = Math.round(player.x);
-    const fy = player.y;
     for (let fire of fireCells) {
-      if (fire.x >= fx - 5 && fire.x <= fx + 5 &&
-          fire.y >= fy - 3 && fire.y <= fy + 2) {
+      if (distance(fire.x, fire.y, player.x, player.y + PLAYER_TANK_Y_FOOTPRINT) <= PLAYER_TANK_BOUNDING_RADIUS + 1) {
         player.energy -= FIRE_DAMAGE * dt;
         player.lastDamageSource = fire.source;
       }

src/weapons.js

@@ -89,7 +89,7 @@ export const EXPLOSION_TYPES = {
     },
     clip(explosion, terrain) {
       const {x, y, cr} = explosion;
-      drawDirt(terrain, x, y, cr);
+      drawDirt(terrain, x, y, cr, terrain.color);
     },
     damage(explosion, player) {}
   },
@@ -139,7 +139,7 @@ export const EXPLOSION_TYPES = {
       const {x, y, cr, osc, pattern} = explosion;
 
       let row = [];
-      for (let cx=0; cx<=1+cr*2; cx++) {
+      for (let cx=0; cx < 1+cr*2; cx++) {
         row.push(randomInt(0, 3) === 0);
       }
       pattern.push(row);