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Old 16th April 2012
xmorg xmorg is offline
Real Name: Tim Cooper
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Question Its a math problem isnt it?

I must have been sleeping in word problem class. Problem: I am trying to move a sprite to the mouse click coordinates with SDL.

Every iteration I use this function (if game mode is hero moving)

Code:
draw_sprites(gr, player, pdirection, ???, ??? ); //<----

void draw_sprites(GameRes *gr, Actor *a, int direction, int movex, int movey) {
  //GameRes*gr is a pointer to struct holding lots of game resources
  //int direction is only being used for which frame(s) our sprite should be displaying
  //Actor *a points to the player sprite, only x/y relevant

  gr->rcSprite->x += movex; //<-----
  gr->rcSprite->y += movey;
  //A lot of sprite frame code below
Now every time I click the mouse I get a x and y from the mouse click, lets just say mousecx, and mousecy I also have and x and y from the player sprites rectangle(rcSprite->x and rcSprite->y) Now, how do I move my rect to the mouse click coordinates? I need it to move incrementally every iteration until it reaches its destination. Maybe its Geometry? CPCTE???

I put my code up on my site
http://www.cooperlabs.net/packages/sdldf.tar.gz
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Old 16th April 2012
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roddierod roddierod is offline
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If I'm reading your question correctly...

Add one(or what every you want your increment to be) to the x and y of the sprite until it equals the the x and y of the mouse.
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Old 17th April 2012
teig teig is offline
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Assuming you want your sprite to move in a straight line, you would need to calculate the line between the two points and select a number of points on that line and move to them in each iteration.
Sounds simple doesn't it!
Or look as the line as a vector, (vx, vy), divide by, say 10, and add deltavx,vy to your sprite 10 times. And then make sure it doesn't go past mousex,y in the last iteration.
Something like that.
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Old 17th April 2012
xmorg xmorg is offline
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So basically, a lot of if/else logic, accounting for every direction?

like so:
Code:
if(gc->mousecx < gr->rcSprite->x && gc->mousecy < gr->rcSprite->y)
	    {}
	  else if(gc->mousecx > gr->rcSprite->x && gc->mousecy > gr->rcSprite->y)
	    {}
	  else if(gc->mousecx < gr->rcSprite->x && gc->mousecy > gr->rcSprite->y)
	    {}
	  else if(gc->mousecx > gr->rcSprite->x && gc->mousecy < gr->rcSprite->y)
	    {}
	  if(gc->mousecx > gr->rcSprite->x) 
	    {player->screen_x = 1; pdirection = EAST; player->moving = 1;}
	  else if(gc->mousecx < gr->rcSprite->x) 
	    {player->screen_x = -1; pdirection = WEST; player->moving = 1;}
	  else if( gr->rcSprite->x == gc->mousecx ) 
	    {player->screen_x = 0; player->moving=0; gamestate = GAME_HERO_SELECTED;}
	  else if(gc->mousecy > gr->rcSprite->y) 
	    {player->screen_y = 1; pdirection = SOUTH; player->moving = 1;}
	  else if(gc->mousecy < gr->rcSprite->y) 
	    {player->screen_y = -1; pdirection = NORTH; player->moving = 1;}
	  else if( gr->rcSprite->y == gc->mousecy ) 
	    {player->screen_y = 0; player->moving=0; gamestate = GAME_HERO_SELECTED;} //dont move
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