Some tweaks to player kinematics

constants.ts

@@ -2,15 +2,15 @@
 // If you want to make some simple tweaks, then here might be the place to start.
 
 const CONST = {
-    GRAVITY: 1000,  // Gravity in pixels per second²
     SCREEN_WIDTH: 1024, 
     SCREEN_HEIGHT: 768,
-    EXPLOSION_FORCE: 10000000,
+    GRAVITY: 1000,  // Gravity in pixels per second²
+    EXPLOSION_FORCE: 10000000, // impulse caused by rocket explosions
     EXPLOSION_MIN_RADIUS: 50, //radius in pixels from within the maximum explosion force is applied
     EXPLOSION_MAX_RADIUS: 500, //radius in pixels from without explosions are completely ignored
     PLAYER_ACCEL_GROUND: 2000, // player acceleration on ground
-    PLAYER_FRICTION_GROUND: 0.9, // fraction of speed the player loses per second while grounded
-    PLAYER_FRICTION_AIR: 0.05, // fraction of speed the player loses per second while airborne
+    PLAYER_FRICTION_GROUND: 0.999, // fraction of speed the player loses per second while grounded
     PLAYER_ACCEL_AIR: 1000, // player acceleration while airborne
-    PLAYER_GROUND_BOUNCE: 0.5 // how much the player bounces when impacting the ground
+    PLAYER_FRICTION_AIR: 0.7, // fraction of speed the player loses per second while airborne
+    PLAYER_GROUND_BOUNCE: 0.75 // how much the player bounces when impacting the ground
 }

player.ts

@@ -36,7 +36,7 @@ class Player extends Entity {
         if (this.isGrounded) {
             frictionFraction = Math.pow((1 - CONST.PLAYER_FRICTION_GROUND), deltaTime )
         } else {
-            frictionFraction = Math.pow((1 - CONST.PLAYER_FRICTION_GROUND), deltaTime )
+            frictionFraction = Math.pow((1 - CONST.PLAYER_FRICTION_AIR), deltaTime )
         }
         this.velocity.x *= frictionFraction
         this.velocity.y *= frictionFraction

renderer.ts

@@ -28,7 +28,9 @@ class Renderer {
         // objects
         state.entities.forEach(r => {
             if (r.sprite) {
-                this.ctx.drawImage(r.sprite, r.pos.x + offset.x - r.renderPivot.x, r.pos.y + offset.y - r.renderPivot.y )
+                let x = Math.round(r.pos.x + offset.x - r.renderPivot.x)
+                let y = Math.round(r.pos.y + offset.y - r.renderPivot.y)
+                this.ctx.drawImage(r.sprite,x ,y )
             }
         })