sprite_index not working gamemaker studio 2 (GML) - gml

Question

I have a small script that changes the sprite index when I press a certain key.
if (key_right)
{
sprite_index = playerRightSpr;//<-------------
image_speed = 1; //|
} //|
if (key_left) //|
{ //|
sprite_index = playerLeftSpr; //|
image_speed = 1; //|
} //|
if (key_left) && (key_right) //|
{ //|
sprite_index = playerSpr; //|
image_speed = 0; //|
} //|
if (!key_right or key_left) //add this and this, doesn't work
{ //but it does when I remove this code.
sprite_index = playerSpr;
image_speed = 0;
}
Is there another way to say when standing still make sprite playerSpr because the way i'm trying seems to cause conflict.
Thanks in advance
Bhodi

Answer 1

If your entity moves you can just use the speed variable to make this.
For example :
if your entity has a positive speed (go right) you will use PlayerRightSpr
if your entity has a negative speed (go left) you will use PlayerLeftSpr
And if speed is 0 you use PlayerSpr
(Instead of using two different sprites you can use image_xscale too)
image_xscale = 1; (normal sprite)
image_xscale = -1; (flip on x axis : mirror)
And finally instead of this :
if (!key_right or key_left)
Use this :
if (!key_right || !key_left)
Or this :
if (key_right == 0 || key_left == 0)
But you are right it's not the correct way to do this
I hope this way is good

Answer 2

Here's my second solution. This went from my own project, so it does require changing the whole code.
I've explained each section with comments next to each lines.
Step event:
var hinput = 0; //hinput = Horizontal Input
hinput = keyboard_check(vk_right) - keyboard_check(vk_left); //the trick I've used to declare the movement system, based on the arrow keys.
//pressing right = 1, pressing left = -1, pressing both or none = 0.
if (hinput != 0) //it is not 0, so the player is moving
{
sprite_index = s_player_walk; //changes the current sprite to the walking animation
image_xscale = hinput; //changes the direction it's facing: 1 = right, -1 = left.
//when it's 0, it keeps the last direction it faced.
}
else //the player is not moving
{
sprite_index = s_player_idle; //changes the current sprite to the idle animation
}
As for the images itself. I've used 2 seperate sprites for this: s_player_idle, which exists of only 1 frame, and s_player_walk, which exists of 3 looping frames.
The image speed is already defined in the image editor for each seperate sprite, so it doesn't need to be defined again in the code.