//sprite structure
typedef struct
{
int x,y;
int movex,movey;
int origY;
int gravity;
} SPRITE;
//player state
enum State
{
Walking,
Jumping
};
//Init sprites properties
image.x = 50;
image.y = 204;
image.movex = 5;
image.movey = 5;
image.origY = 0;
image.gravity = 9.81;
if(KEY_DOWN(VK_LEFT))
image.x -= image.movex;
if(KEY_DOWN(VK_RIGHT))
image.x += image.movex;
if(KEY_DOWN(VK_SPACE))
{
//Jump logic goes here
}
// I am going to use C++ in this example:struct Sprite{ int position_x, position_y; int velocity_x, velocity_y; int acceleration_y; // you can include x acceleration if you wish int runspeed, jumpspeed; bool inAir; // this neatly covers jumping and falling. // other stuff};bool hitsGround(const Sprite &sprite, /* ... other parameters ... */){ // whatever logic to work out if a sprite is on the ground}int main(){ Sprite player; // set the values here, or use a constructor call // ... while(running) { // input if(key_down(VK_LEFT)) { player.velocity_x = -player.runspeed; } else if(key_down(VK_RIGHT)) { player.velocity_x = player.runspeed; } else { player.velocity_x = 0; } if(key_down(VK_SPACE)) { player.velocity_y = 0; player.acceleration_y = player.jumpspeed; player.inAir = true; } // game logic if( player.inAir ) { player.velocity_y += player.acceleration_y; player.acceleration_y -= /* gravity value */; if( hitsGround(player, /* any other info needed */) ) { player.inAir = false; } } player.position_x += player.velocity_x; player.position_y += player.velocity_y; // drawing and other code }}Quote:Original post by wicked357
Well actually the whole intention to this program was to make it jump moving forward and backwards is easy, that was just added because I want to be able to jump in the direction I am going so if I am standing still I jump up and fall down, if I am walking right I make a right jump and so on... The last 3 weeks I have been using c++ and directx to make games and so far I can do all the basics needed like load sprites load surfaces draw them and make them move, I thought I should move on to the next which was jumping and I have been stuck all day. I am been looking up different kinds of AI and mathematics, but still no luck that shows the exact easy to understand theory on gravity. Let me reiterate that I started directx/c++ programming 3 weeks ago I have taken 3 c++ classes already, but I have been doing mainly C# in the last 6 months.
Quote:Original post by ExcessNeo
Mr. Accident Acceleration is constant yes being -9.81m/s/s however you can't just decide to end acceleration mid-air until you have reached terminal velocity, rip-off's example is a bit strange though having another look.
