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VECTOR ladder_x;
VECTOR player_diff;
VECTOR temp;

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var movement_mode = 0;
var player_feet_height = 32; //the distance from the origin to the feet of the player 
var z_force = 0; 
var jump_z;

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#define animdist skill20

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function detect_edge()
{
	my.animdist = 0; 
	if (movement_mode == 0)
	{
		vec_set(temp,my.x); //scan in front of player to see if there is a climbable wall 
		temp.x += 30 * cos(my.pan); 
		temp.y += 30 * sin(my.pan); 
		temp.z = my.z; 
		result = c_trace(my.x,temp,IGNORE_ME|IGNORE_SPRITES|IGNORE_MODELS|SCAN_TEXTURE); 
		vec_set(temp,my.x); 
		temp.z -= 4000; // calculate a position 4000 quants below the player 
		// set a trace mode for using the player's hull, and detecting map entities and level surfaces only 
		result = c_trace(my.x,temp,IGNORE_ME|IGNORE_SPRITES|IGNORE_MODELS|USE_BOX);// subtract vertical distance to ground 
		if (result <= 3)
		{
			// in the air? 
			if ((result < 1.3) && (result > -1.3) && (result > 0.5) && (result < -0.5))
			{
				//change the value 1.5 to change how high steps he can climb, make it no higher than 3 
				my.skill13 = 0; 
			} 
			vec_set(temp,my.x); 
			temp.z -= 4000; // calculate a position 4000 quants below the player 
			result = c_trace(my.x,temp,IGNORE_ME|IGNORE_SPRITES|IGNORE_MODELS|USE_BOX);
			// subtract vertical distance to ground 
			z_force = -1 * result; 
		}
		else
		{
			if ((result <= 3) && (my.animdist > 20))
			{
				if ((result < 1.3) && (result > -1.3) && (result > 0.5) && (result < -0.5))
				{
					//change the value 1.5 to change how high steps he can climb, make it no higher than 3 
					my.skill13 = 0; 
				} 
				vec_set(temp,my.x); 
				temp.z -= 4000; // calculate a position 4000 quants below the player 
				result = c_trace(my.x,temp,IGNORE_ME|IGNORE_SPRITES|IGNORE_MODELS|USE_BOX);// subtract vertical distance to ground 
				z_force = -1 * result; 
			}
		} 
		if ((key_w == 1) || (key_s == 1) || (key_d == 1) || (key_a == 1))
		{
			if (key_shift == 0) 
			{
				ent_animate(my,"run",my.animdist,ANM_CYCLE); 
				my.animdist += 10 * time_step; 
			}
			else
			{
				ent_animate(my,"walk",my.animdist,ANM_CYCLE); 
				my.animdist += 9 * time_step; 
			} 
		} 
		else
		{
			ent_animate(my,"stand",my.animdist,ANM_CYCLE); 
			my.animdist += 3 * time_step; 
		} 
		my.skill13 = 0.5*z_force + maxv(1-0.5*0.7,0)*my.skill13; // calculate vertical speed, replace 0.3 with time to convert to the old equation 
		jump_z = time_step * my.skill13; // distance down 
		player_diff.z = jump_z; 
		c_move(my,player_diff, nullvector,IGNORE_PASSABLE|GLIDE); 
		//center_check(); 
		//update_views(); 
	} 
	if (movement_mode == 2) 
	{
		//pulling yourself up onto a ledge 
		my.z += 5 * time_step; 
		player_diff.x = 1; 
		player_diff.y = 0; 
		player_diff.z = 0; 
		c_move(my,player_diff.x,nullvector,IGNORE_PASSABLE|GLIDE); 
		vec_set(temp,my.x); //scan in front of player to see if there is a climbable wall 
		temp.x += 30 * cos(my.pan); 
		temp.y += 30 * sin(my.pan); 
		temp.z = my.z - player_feet_height; //set the value 32 to the distance to the models feet 
		if(c_trace(my.x,temp,IGNORE_ME|IGNORE_SPRITES|IGNORE_MODELS) == 0) 
		{
			movement_mode = 3; 
			vec_set(ladder_x.x,my.x); 
		} 
		ent_animate(my,"walk",my.animdist,ANM_CYCLE); // edge climb animation here 
		my.animdist += 9 * time_step; // 9 is climbing speed
		//center_check(); 
		//update_views(); 
	}
	if (movement_mode == 3) 
	{
		//moving a little bit forward so that player doesn't fall down 
		player_diff.x = 3 * time_step; 
		player_diff.y = 0; 
		vec_set(temp,my.x); 
		temp.z -= 4000; // calculate a position 4000 quants below the player 
		// set a trace mode for using the player's hull, and detecting map entities and level surfaces only 
		result = c_trace(my.x,temp,IGNORE_ME|IGNORE_SPRITES|IGNORE_MODELS|USE_BOX);// subtract vertical distance to ground 
		player_diff.z = 0; 
		if (result < 4) { player_diff.z = -0.2 * result; } 
		if(vec_dist(my.x,ladder_x.x) > 7) 
		{
			vec_set(temp,my.x); 
			temp.z -= 4000; // calculate a position 4000 quants below the player 
			// set a trace mode for using the player's hull, and detecting map entities and level surfaces only 
			result = c_trace(my.x,temp,IGNORE_ME|IGNORE_SPRITES|IGNORE_MODELS|USE_BOX);// subtract vertical distance to ground 
			if (result < 4) { player_diff.z = -1 * result; } 
		}
		else
		{
			player_diff.z = 0; 
		} 
		c_move(my,player_diff, nullvector, IGNORE_PASSABLE|GLIDE); 
		if(vec_dist(my.x,ladder_x.x) > 15) 
		{
			movement_mode = 0; 
			player_diff.z = 0; 
			//z_force = 0; 
			my.skill13 = 0; 
		} 
		ent_animate(my,"walk",my.animdist,ANM_CYCLE); 
		my.animdist += 9 * time_step; 
		//center_check(); 
		//update_views(); 
	}
}