Wall jumping collision detection anomaly

Question

I'm creating a game where the player ascends a tower by wall jumping his way to the top. When the player has collided with the right wall they can only jump left and vice versa. Here is my current implementation:

    if(wallCollision() == "left"){
        player.setPosX(0);
        player.setVelX(0);
        ignoreCollisions = true;
        player.setCanJump(true);
        player.setFacingLeft(false);
    } else if (wallCollision() == "right"){
        player.setPosX(screenWidth-playerWidth*2);
        player.setVelX(0);
        ignoreCollisions = true;
        player.setCanJump(true);
        player.setFacingLeft(true);
    } else{
        player.setVelY(player.getVelY() + gravity);
    } 

and

private String wallCollision(){
    if(player.getPosX() < playerWidth && !ignoreCollisions)
        return "left";
    else if(player.getPosX() > screenWidth - playerWidth*2 && !ignoreCollisions)
        return "right";
    else{       
        timeToJump += Gdx.graphics.getDeltaTime();
        if(timeToJump > 0.50f){
            timeToJump = 0;
            ignoreCollisions = false;
        }
        return "jumping";
    }
}

If the player is colliding with the left wall it will switch between the states left and jumping repeatedly due to the varible ignoreCollisions being switched repeatedly in collision checks. This will give a chance to either jump as intended or simply ascend vertically instead of diagonally.

I can't figure out an implementation that will reliably make sure the player jumps as intended. Does anyone have any pointers?

Answer 1

It seems your left limit for detecting collision is playerWidth, but when you detect a collision on the left, you reset the x coordinate to 0.

if(wallCollision() == "left"){
    player.setPosX(0); //Should be player.setPosX(playerWidth);

[EDIT]

After seen your images I notice playerWidth actually represents half the player width, and your character X coordinate is that of it's left side. In that case, try this, detect left collision when player.getPosX() < 0, and reset the pos to 0 as you're doing now:

if(wallCollision() == "left"){
    player.setPosX(0);
    player.setVelX(0);
    ignoreCollisions = true;
    player.setCanJump(true);
    player.setFacingLeft(false);
} else if (wallCollision() == "right"){
    player.setPosX(screenWidth-playerWidth*2);
    player.setVelX(0);
    ignoreCollisions = true;
    player.setCanJump(true);
    player.setFacingLeft(true);
} else{
    player.setVelY(player.getVelY() + gravity);
} 

and:

private String wallCollision(){
    if(player.getPosX() < 0 && !ignoreCollisions)
        return "left";
    else if(player.getPosX() > screenWidth - playerWidth*2 && !ignoreCollisions)
        return "right";
    else{       
        timeToJump += Gdx.graphics.getDeltaTime();
        if(timeToJump > 0.50f){
            timeToJump = 0;
            ignoreCollisions = false;
        }
        return "jumping";
    }
}

Answer 2

I agree with @jspurim that your collision bounds checking, but that is another matter. You are asking about inconsistent jumping off of walls due to the ignoreCollision flag flip-flopping, right?

From what I gather reading the code you have posted, when the player jumps and collides with a wall, they stick to that wall and begin to climb vertically. After a brief moment the player can then jump off the wall, or continue climbing the wall they are currently stuck to. The flip-flopping is happening because after the short pause you say it is ok to stop ingnoring collision, when in fact the player is still running up the wall and there is no need to check for wall collisions yet.

Try moving ignoreCollisions = false; out of wallCollision() and put it in the code where the player actually jumps off of the wall.