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### #ActualBeerNutts

Posted 05 June 2014 - 01:41 PM

Warnexus, I assume, if your player steps off a platform and is falling, he won't be able to jump while falling right?  What I'm trying to get at is, you might need a generic solution which works whether you've just jumped or you're falling.

I'd suggest looking at trying to use a IsOnGround flag, unless you have a special can jump in mid air ability.

I managed to fix it. I decided to write a logic that tells the game that the character is off the block. So I can do something like this:

if(!onBlock && getY() + idleRightAnim.getHeight() < Screen.HEIGHT - 35)
{
if(state != ActionState.JUMPING)
{
state = ActionState.FALLING;
}
}


That's a little better, but, you still should be trying to use a more generic solution.  Why have a jumping state, or a falling state?  Why not determine if a player is jumping or falling based on his Y velocity.  You can use some simple physics to figure out if your character is jump, falling or standing.

Here's simple code to get you thinking about other options

// some numbers I made up
#define GRAVITY 5.0
#define JUMP_Y_VELOCITY -50.0
#define MOVE_VELOCITY 8.0

void Character::Update()
{
int tempYVelocity = m_Velocity.y;
int tempXVelocity = m_Velocity.x;
int tempYPos = m_Pos.y;
int tempXPos = m_Pos.x;

// all input's require used to be on the ground (unless you want character to move while in the air)
if (m_IsOnGround)
// if user has pressed Jump, and he's on the ground, jump
if (Input.KeyPressed(JUMP_KEY)) {
tempYVelocity = JUMP_Y_VELOCITY;
}

// Change X velocity based on key pressed
if (Input.KeyPressed(MOVE_LEFT_KEY)) {
tempXVelocity = -MOVE_VELOCITY;
}
if (Input.KeyPressed(MOVE_RIGHT_KEY)) {
tempXVelocity = MOVE_VELOCITY;
}
}
// move character horizontally
tempXPos += tempXVelocity

// check if moving him caused a collision
if (CheckCollision(tempXPos, tempYPos, m_Size.x, m_Size.y)) {
// reset location
tempXPos = m_Pos.x;
}

// always apply gravity to the characters
tempYVelocity += GRAVITY;
tempYPos += tempYVelocity;

// after moving Y position, check if we've hit anything, using location and size of the character
bool isYcollision = CheckCollision(tempXPos, tempYPos, m_Size.x, m_Size.y);

// check if the velocity is downwards (positive), and if the player collided with anything, then we're on the ground; reset velocity to 0
// if velocity is downwards, then we're falling...
if (tempYVelocity > 0) {
// if the player collided with anything, then we're on the ground; reset velocity to 0, and move player back to original posiiton
if (isYcollision) {
m_IsOnGround = true;
tempYPos = m_Pos.y;
tempYVelocity = 0.0;
}
else {
// we're falling
m_AnimationState = FALLING;
m_IsOnGround = false;
}
}
else {
// else we're jumping, but check if we hit our head on anything
if (isYcollision) {
// reset YVelocity to 0, but change state to falling
tempYVelocity = 0.0;
m_AnimationState = FALLING;
}
else {
// we're going up, so show jumping
m_AnimationState = Jumping;
m_IsOnGround = false;
}

// set all the member variables to temp variables
m_Velocity.y = tempYVelocity;
m_Pos.y = tempYPos;
m_Velocity.x = tempXVelocity;
m_Pos.x = tempXPos;
}


This is just a sample to get you to think about generic ways of determining what a character is doing.

### #2BeerNutts

Posted 05 June 2014 - 01:40 PM

Warnexus, I assume, if your player steps off a platform and is falling, he won't be able to jump while falling right?  What I'm trying to get at is, you might need a generic solution which works whether you've just jumped or you're falling.

I'd suggest looking at trying to use a IsOnGround flag, unless you have a special can jump in mid air ability.

I managed to fix it. I decided to write a logic that tells the game that the character is off the block. So I can do something like this:

if(!onBlock && getY() + idleRightAnim.getHeight() < Screen.HEIGHT - 35)
{
if(state != ActionState.JUMPING)
{
state = ActionState.FALLING;
}
}


That's a little better, but, you still should be trying to use a more generic solution.  Why have a jumping state, or a falling state?  Why not determine if a player is jumping or falling based on his Y velocity.  You can use some simple physics to figure out if your character is jump, falling or standing.

Here's simple code to get you thinking about other options

// some numbers I made up
#define GRAVITY -5.0
#define JUMP_Y_VELOCITY 50.0
#define MOVE_VELOCITY 8.0

void Character::Update()
{
int tempYVelocity = m_Velocity.y;
int tempXVelocity = m_Velocity.x;
int tempYPos = m_Pos.y;
int tempXPos = m_Pos.x;

// all input's require used to be on the ground (unless you want character to move while in the air)
if (m_IsOnGround)
// if user has pressed Jump, and he's on the ground, jump
if (Input.KeyPressed(JUMP_KEY)) {
tempYVelocity = JUMP_Y_VELOCITY;
}

// Change X velocity based on key pressed
if (Input.KeyPressed(MOVE_LEFT_KEY)) {
tempXVelocity = -MOVE_VELOCITY;
}
if (Input.KeyPressed(MOVE_RIGHT_KEY)) {
tempXVelocity = MOVE_VELOCITY;
}
}
// move character horizontally
tempXPos += tempXVelocity

// check if moving him caused a collision
if (CheckCollision(tempXPos, tempYPos, m_Size.x, m_Size.y)) {
// reset location
tempXPos = m_Pos.x;
}

// always apply gravity to the characters
tempYVelocity += GRAVITY;
tempYPos += tempYVelocity;

// after moving Y position, check if we've hit anything, using location and size of the character
bool isYcollision = CheckCollision(tempXPos, tempYPos, m_Size.x, m_Size.y);

// check if the velocity is downwards (negative), and if the player collided with anything, then we're on the ground; reset velocity to 0
// if velocity is downwards, then we're falling...
if (tempYVelocity < 0) {
// if the player collided with anything, then we're on the ground; reset velocity to 0, and move player back to original posiiton
if (isYcollision) {
m_IsOnGround = true;
tempYPos = m_Pos.y;
tempYVelocity = 0.0;
}
else {
// we're falling
m_AnimationState = FALLING;
m_IsOnGround = false;
}
}
else {
// else we're jumping, but check if we hit our head on anything
if (isYcollision) {
// reset YVelocity to 0, but change state to falling
tempYVelocity = 0.0;
m_AnimationState = FALLING;
}
else {
// we're going up, so show jumping
m_AnimationState = Jumping;
m_IsOnGround = false;
}

// set all the member variables to temp variables
m_Velocity.y = tempYVelocity;
m_Pos.y = tempYPos;
m_Velocity.x = tempXVelocity;
m_Pos.x = tempXPos;
}


This is just a sample to get you to think about generic ways of determining what a character is doing.

### #1BeerNutts

Posted 05 June 2014 - 09:51 AM

Warnexus, I assume, if your player steps off a platform and is falling, he won't be able to jump while falling right?  What I'm trying to get at is, you might need a generic solution which works whether you've just jumped or you're falling.

I'd suggest looking at trying to use a IsOnGround flag, unless you have a special can jump in mid air ability.

I managed to fix it. I decided to write a logic that tells the game that the character is off the block. So I can do something like this:

if(!onBlock && getY() + idleRightAnim.getHeight() < Screen.HEIGHT - 35)
{
if(state != ActionState.JUMPING)
{
state = ActionState.FALLING;
}
}


That's a little better, but, you still should be trying to use a more generic solution.  Why have a jumping state, or a falling state?  Why not determine if a player is jumping or falling based on his Y velocity.  You can use some simple physics to figure out if your character is jump, falling or standing.

Here's simple code to get you thinking about other options

// some numbers I made up
#define GRAVITY -5.0
#define JUMP_Y_VELOCITY 50.0
#define MOVE_VELOCITY 8.0

void Character::Update()
{
int tempYVelocity = m_Velocity.y;
int tempXVelocity = m_Velocity.x;
int tempYPos = m_Pos.y;
int tempXPos = m_Pos.x;

// all input's require used to be on the ground (unless you want character to move while in the air)
if (m_IsOnGround)
// if user has pressed Jump, and he's on the ground, jump
if (Input.KeyPressed(JUMP_KEY) && m_IsOnGround) {
tempYVelocity = JUMP_Y_VELOCITY;
}

// Change X velocity based on key pressed (remove IsOnGround check if you want to mvoe in the air)
if (Input.KeyPressed(MOVE_LEFT_KEY) && IsOnGround) {
tempXVelocity = -MOVE_VELOCITY;
}
if (Input.KeyPressed(MOVE_RIGHT_KEY) && IsOnGround) {
tempXVelocity = MOVE_VELOCITY;
}
// move character horizontally
tempXPos += tempXVelocity

// check if moving him caused a collision
if (CheckCollision(tempXPos, tempYPos, m_Size.x, m_Size.y)) {
// reset location
tempXPos = m_Pos.x;
}

// always apply gravity to the characters
tempYVelocity += GRAVITY;
tempYPos += tempYVelocity;

// after moving Y position, check if we've hit anything, using location and size of the character
bool isYcollision = CheckCollision(tempXPos, tempYPos, m_Size.x, m_Size.y);

// check if the velocity is downwards (negative), and if the player collided with anything, then we're on the ground; reset velocity to 0
// if velocity is downwards, then we're falling...
if (tempYVelocity < 0) {
// if the player collided with anything, then we're on the ground; reset velocity to 0, and move player back to original posiiton
if (isYcollision) {
m_IsOnGround = true;
tempYPos = m_Pos.y;
tempYVelocity = 0.0;
}
else {
// we're falling
m_AnimationState = FALLING;
m_IsOnGround = false;
}
}
else {
// else we're jumping, but check if we hit our head on anything
if (isYcollision) {
// reset YVelocity to 0, but change state to falling
tempYVelocity = 0.0;
m_AnimationState = FALLING;
}
else {
// we're going up, so show jumping
m_AnimationState = Jumping;
m_IsOnGround = false;
}

// set all the member variables to temp variables
m_Velocity.y = tempYVelocity;
m_Pos.y = tempYPos;
m_Velocity.x = tempXVelocity;
m_Pos.x = tempXPos;
}


This is just a sample to get you to think about generic ways of determining what a character is doing.

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