index : minetest.git	gpcf lifo-fixes release
	modified minetest for gpcfs purposes	gpcf

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path: root/builtin/mainmenu/dlg_create_world.lua

	Commit message (Expand)	Author	Age
*	Add support for 'seed' in disallow_mapgen_settings (#12023)	Wuzzy	2022-02-12
*	Mainmenu game-related changes (#11887)	sfan5	2022-01-09
*	Allow for Game-Specific Menu Music (#11241)	ExeVirus	2021-11-22
*	Replace 'minetest.' with 'core.' in builtin	rubenwardy	2021-02-11
*	Add dependency resolution to ContentDB (#9997)	rubenwardy	2020-12-23
*	Give unnamed world names incrementing numbers. Format 'world<number>' (#10247)	Paramat	2020-10-13
*	Mapgen Flat: Add caverns, disabled by default (#9913)	Paramat	2020-08-05
*	Rename “Minimal development test” to “Development Test” (#9928)	Wuzzy	2020-05-26
*	Add mapgen settings to world creation dialog (#9254)	Wuzzy	2020-05-12
*	Add allowed_mapgens option in game.conf. (#9263)	Wren Turkal	2020-04-06
*	Fix undeclared global warning because of _ (#8798)	DS	2019-08-14
*	Add luacheck to check builtin (#7895)	rubenwardy	2019-08-06
*	Make advanced settings noiseparams strings translatable (#8062)	Wuzzy	2019-01-20
*	Add online content repository	rubenwardy	2018-04-19
*	Rename 'subgame' to 'game'	paramat	2018-03-13
*	Fix error if setting menu_last_game is not a valid game	nOOb3167	2017-12-22
*	Give subgames the ability to disallow specific mapgens (#6792)	Ezhh	2017-12-16
*	Make world creation menu automatically generate a random world name (#6257)	lisacvuk	2017-08-18
*	Use a settings object for the main settings	ShadowNinja	2017-05-06
*	Mainmenu: Standardize the menu button order and sizes	SmallJoker	2016-04-28
*	Fix map_seed not changed when creating a new world after login to another	fz72	2015-02-18
*	Add core.get_mapgen_names() to Main Menu API (and use it)	kwolekr	2014-12-29
*	Add mgv5. New noise code, uses biome API. Eased 3d noise for terrain, caves, ...	paramat	2014-11-08
*	Add notice when only minimal is installed	rubenwardy	2014-10-28
*	Formspec escape fixed seen in world creation menu	ShadowNinja	2014-08-05
*	Remove indev mapgen	proller	2014-07-12
*	Remove math mapgen	proller	2014-07-12
*	Add formspec toolkit and refactor mainmenu to use it	sapier	2014-05-16

generated by cgit v1.2.3 (git 2.39.1) at 2025-01-31 19:10:23 +0000

/*
Minetest
Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#include "localplayer.h"

#include "event.h"
#include "collision.h"
#include "gamedef.h"
#include "nodedef.h"
#include "settings.h"
#include "environment.h"
#include "map.h"
#include "client.h"

/*
	LocalPlayer
*/

LocalPlayer::LocalPlayer(Client *gamedef, const char *name):
	Player(name, gamedef->idef()),
	parent(0),
	hp(PLAYER_MAX_HP),
	got_teleported(false),
	isAttached(false),
	touching_ground(false),
	in_liquid(false),
	in_liquid_stable(false),
	liquid_viscosity(0),
	is_climbing(false),
	swimming_vertical(false),
	// Movement overrides are multipliers and must be 1 by default
	physics_override_speed(1.0f),
	physics_override_jump(1.0f),
	physics_override_gravity(1.0f),
	physics_override_sneak(true),
	physics_override_sneak_glitch(true),
	overridePosition(v3f(0,0,0)),
	last_position(v3f(0,0,0)),
	last_speed(v3f(0,0,0)),
	last_pitch(0),
	last_yaw(0),
	last_keyPressed(0),
	last_camera_fov(0),
	last_wanted_range(0),
	camera_impact(0.f),
	last_animation(NO_ANIM),
	hotbar_image(""),
	hotbar_selected_image(""),
	light_color(255,255,255,255),
	hurt_tilt_timer(0.0f),
	hurt_tilt_strength(0.0f),
	m_position(0,0,0),
	m_sneak_node(32767,32767,32767),
	m_sneak_node_exists(false),
	m_need_to_get_new_sneak_node(true),
	m_sneak_node_bb_ymax(0),
	m_old_node_below(32767,32767,32767),
	m_old_node_below_type("air"),
	m_can_jump(false),
	m_breath(PLAYER_MAX_BREATH),
	m_yaw(0),
	m_pitch(0),
	camera_barely_in_ceiling(false),
	m_collisionbox(-BS * 0.30, 0.0, -BS * 0.30, BS * 0.30, BS * 1.75, BS * 0.30),
	m_cao(NULL),
	m_gamedef(gamedef)
{
	// Initialize hp to 0, so that no hearts will be shown if server
	// doesn't support health points
	hp = 0;
	eye_offset_first = v3f(0,0,0);
	eye_offset_third = v3f(0,0,0);
}

LocalPlayer::~LocalPlayer()
{
}

void LocalPlayer::move(f32 dtime, Environment *env, f32 pos_max_d,
		std::vector<CollisionInfo> *collision_info)
{
	Map *map = &env->getMap();
	INodeDefManager *nodemgr = m_gamedef->ndef();

	v3f position = getPosition();

	// Copy parent position if local player is attached
	if(isAttached)
	{
		setPosition(overridePosition);
		m_sneak_node_exists = false;
		return;
	}

	// Skip collision detection if noclip mode is used
	bool fly_allowed = m_gamedef->checkLocalPrivilege("fly");
	bool noclip = m_gamedef->checkLocalPrivilege("noclip") &&
		g_settings->getBool("noclip");
	bool free_move = noclip && fly_allowed && g_settings->getBool("free_move");
	if (free_move) {
		position += m_speed * dtime;
		setPosition(position);
		m_sneak_node_exists = false;
		return;
	}

	/*
		Collision detection
	*/

	bool is_valid_position;
	MapNode node;
	v3s16 pp;

	/*
		Check if player is in liquid (the oscillating value)
	*/

	// If in liquid, the threshold of coming out is at higher y
	if (in_liquid)
	{
		pp = floatToInt(position + v3f(0,BS*0.1,0), BS);
		node = map->getNodeNoEx(pp, &is_valid_position);
		if (is_valid_position) {
			in_liquid = nodemgr->get(node.getContent()).isLiquid();
			liquid_viscosity = nodemgr->get(node.getContent()).liquid_viscosity;
		} else {
			in_liquid = false;
		}
	}
	// If not in liquid, the threshold of going in is at lower y
	else
	{
		pp = floatToInt(position + v3f(0,BS*0.5,0), BS);
		node = map->getNodeNoEx(pp, &is_valid_position);
		if (is_valid_position) {
			in_liquid = nodemgr->get(node.getContent()).isLiquid();
			liquid_viscosity = nodemgr->get(node.getContent()).liquid_viscosity;
		} else {
			in_liquid = false;
		}
	}


	/*
		Check if player is in liquid (the stable value)
	*/
	pp = floatToInt(position + v3f(0,0,0), BS);
	node = map->getNodeNoEx(pp, &is_valid_position);
	if (is_valid_position) {
		in_liquid_stable = nodemgr->get(node.getContent()).isLiquid();
	} else {
		in_liquid_stable = false;
	}

	/*
	        Check if player is climbing
	*/


	pp = floatToInt(position + v3f(0,0.5*BS,0), BS);
	v3s16 pp2 = floatToInt(position + v3f(0,-0.2*BS,0), BS);
	node = map->getNodeNoEx(pp, &is_valid_position);
	bool is_valid_position2;
	MapNode node2 = map->getNodeNoEx(pp2, &is_valid_position2);

	if (!(is_valid_position && is_valid_position2)) {
		is_climbing = false;
	} else {
		is_climbing = (nodemgr->get(node.getContent()).climbable
				|| nodemgr->get(node2.getContent()).climbable) && !free_move;
	}


	/*
		Collision uncertainty radius
		Make it a bit larger than the maximum distance of movement
	*/
	//f32 d = pos_max_d * 1.1;
	// A fairly large value in here makes moving smoother
	f32 d = 0.15*BS;

	// This should always apply, otherwise there are glitches
	sanity_check(d > pos_max_d);

	// Maximum distance over border for sneaking
	f32 sneak_max = BS*0.4;

	/*
		If sneaking, keep in range from the last walked node and don't
		fall off from it
	*/
	if (control.sneak && m_sneak_node_exists &&
			!(fly_allowed && g_settings->getBool("free_move")) && !in_liquid &&
			physics_override_sneak && !got_teleported) {
		f32 maxd = 0.5 * BS + sneak_max;
		v3f lwn_f = intToFloat(m_sneak_node, BS);
		position.X = rangelim(position.X, lwn_f.X-maxd, lwn_f.X+maxd);
		position.Z = rangelim(position.Z, lwn_f.Z-maxd, lwn_f.Z+maxd);

		if (!is_climbing) {
			// Move up if necessary
			f32 new_y = (lwn_f.Y - 0.5 * BS) + m_sneak_node_bb_ymax;
			if (position.Y < new_y)
				position.Y = new_y;
			/*
				Collision seems broken, since player is sinking when
				sneaking over the edges of current sneaking_node.
				TODO (when fixed): Set Y-speed only to 0 when position.Y < new_y.
			*/
			if (m_speed.Y < 0)
				m_speed.Y = 0;
		}
	}

	if (got_teleported)
		got_teleported = false;

	// this shouldn't be hardcoded but transmitted from server
	float player_stepheight = touching_ground ? (BS*0.6) : (BS*0.2);

#ifdef __ANDROID__
	player_stepheight += (0.6 * BS);
#endif

	v3f accel_f = v3f(0,0,0);

	collisionMoveResult result = collisionMoveSimple(env, m_gamedef,
		pos_max_d, m_collisionbox, player_stepheight, dtime,
		&position, &m_speed, accel_f);

	/*
		If the player's feet touch the topside of any node, this is
		set to true.

		Player is allowed to jump when this is true.
	*/
	bool touching_ground_was = touching_ground;
	touching_ground = result.touching_ground;

    //bool standing_on_unloaded = result.standing_on_unloaded;

	/*
		Check the nodes under the player to see from which node the
		player is sneaking from, if any.  If the node from under
		the player has been removed, the player falls.
	*/
	f32 position_y_mod = 0.05 * BS;
	if (m_sneak_node_bb_ymax > 0)
		position_y_mod = m_sneak_node_bb_ymax - position_y_mod;
	v3s16 current_node = floatToInt(position - v3f(0, position_y_mod, 0), BS);
	if (m_sneak_node_exists &&
			nodemgr->get(map->getNodeNoEx(m_old_node_below)).name == "air" &&
			m_old_node_below_type != "air") {
		// Old node appears to have been removed; that is,
		// it wasn't air before but now it is
		m_need_to_get_new_sneak_node = false;
		m_sneak_node_exists = false;
	} else if (nodemgr->get(map->getNodeNoEx(current_node)).name != "air") {
		// We are on something, so make sure to recalculate the sneak
		// node.
		m_need_to_get_new_sneak_node = true;
	}

	if (m_need_to_get_new_sneak_node && physics_override_sneak) {
		m_sneak_node_bb_ymax = 0;
		v3s16 pos_i_bottom = floatToInt(position - v3f(0, position_y_mod, 0), BS);
		v2f player_p2df(position.X, position.Z);
		f32 min_distance_f = 100000.0 * BS;
		// If already seeking from some node, compare to it.
		/*if(m_sneak_node_exists)
		{
			v3f sneaknode_pf = intToFloat(m_sneak_node, BS);
			v2f sneaknode_p2df(sneaknode_pf.X, sneaknode_pf.Z);
			f32 d_horiz_f = player_p2df.getDistanceFrom(sneaknode_p2df);
			f32 d_vert_f = fabs(sneaknode_pf.Y + BS*0.5 - position.Y);
			// Ignore if player is not on the same level (likely dropped)
			if(d_vert_f < 0.15*BS)
				min_distance_f = d_horiz_f;
		}*/
		v3s16 new_sneak_node = m_sneak_node;
		for(s16 x=-1; x<=1; x++)
		for(s16 z=-1; z<=1; z++)
		{
			v3s16 p = pos_i_bottom + v3s16(x,0,z);
			v3f pf = intToFloat(p, BS);
			v2f node_p2df(pf.X, pf.Z);
			f32 distance_f = player_p2df.getDistanceFrom(node_p2df);
			f32 max_axis_distance_f = MYMAX(
					fabs(player_p2df.X-node_p2df.X),
					fabs(player_p2df.Y-node_p2df.Y));

			if(distance_f > min_distance_f ||
					max_axis_distance_f > 0.5*BS + sneak_max + 0.1*BS)
				continue;


			// The node to be sneaked on has to be walkable
			node = map->getNodeNoEx(p, &is_valid_position);
			if (!is_valid_position || nodemgr->get(node).walkable == false)
				continue;
			// And the node above it has to be nonwalkable
			node = map->getNodeNoEx(p + v3s16(0,1,0), &is_valid_position);
			if (!is_valid_position || nodemgr->get(node).walkable) {
				continue;
			}
			if (!physics_override_sneak_glitch) {
				node =map->getNodeNoEx(p + v3s16(0,2,0), &is_valid_position);
				if (!is_valid_position || nodemgr->get(node).walkable)
					continue;
			}

			min_distance_f = distance_f;
			new_sneak_node = p;
		}

		bool sneak_node_found = (min_distance_f < 100000.0 * BS * 0.9);

		m_sneak_node = new_sneak_node;
		m_sneak_node_exists = sneak_node_found;

		if (sneak_node_found) {
			f32 cb_max = 0;
			MapNode n = map->getNodeNoEx(m_sneak_node);
			std::vector<aabb3f> nodeboxes;
			n.getCollisionBoxes(nodemgr, &nodeboxes);
			for (std::vector<aabb3f>::iterator it = nodeboxes.begin();
					it != nodeboxes.end(); ++it) {
				aabb3f box = *it;
				if (box.MaxEdge.Y > cb_max)
					cb_max = box.MaxEdge.Y;
			}
			m_sneak_node_bb_ymax = cb_max;
		}

		/*
			If sneaking, the player's collision box can be in air, so
			this has to be set explicitly
		*/
		if(sneak_node_found && control.sneak)
			touching_ground = true;
	}

	/*
		Set new position
	*/
	setPosition(position);

	/*
		Report collisions
	*/

	// Dont report if flying
	if(collision_info && !(g_settings->getBool("free_move") && fly_allowed)) {
		for(size_t i=0; i<result.collisions.size(); i++) {
			const CollisionInfo &info = result.collisions[i];
			collision_info->push_back(info);
		}
	}

	if(!result.standing_on_object && !touching_ground_was && touching_ground) {
		MtEvent *e = new SimpleTriggerEvent("PlayerRegainGround");
		m_gamedef->event()->put(e);

		// Set camera impact value to be used for view bobbing
		camera_impact = getSpeed().Y * -1;
	}

	{
		camera_barely_in_ceiling = false;
		v3s16 camera_np = floatToInt(getEyePosition(), BS);
		MapNode n = map->getNodeNoEx(camera_np);
		if(n.getContent() != CONTENT_IGNORE){
			if(nodemgr->get(n).walkable && nodemgr->get(n).solidness == 2){
				camera_barely_in_ceiling = true;
			}
		}
	}

	/*
		Update the node last under the player
	*/
	m_old_node_below = floatToInt(position - v3f(0,BS/2,0), BS);
	m_old_node_below_type = nodemgr->get(map->getNodeNoEx(m_old_node_below)).name;

	/*
		Check properties of the node on which the player is standing
	*/
	const ContentFeatures &f = nodemgr->get(map->getNodeNoEx(getStandingNodePos()));
	// Determine if jumping is possible
	m_can_jump = touching_ground && !in_liquid;
	if(itemgroup_get(f.groups, "disable_jump"))
		m_can_jump = false;
	// Jump key pressed while jumping off from a bouncy block
	if (m_can_jump && control.jump && itemgroup_get(f.groups, "bouncy") &&
		m_speed.Y >= -0.5 * BS) {
		float jumpspeed = movement_speed_jump * physics_override_jump;
		if (m_speed.Y > 1) {
			// Reduce boost when speed already is high
			m_speed.Y += jumpspeed / (1 + (m_speed.Y / 16 ));
		} else {
			m_speed.Y += jumpspeed;
		}
		setSpeed(m_speed);
		m_can_jump = false;
	}
}

void LocalPlayer::move(f32 dtime, Environment *env, f32 pos_max_d)
{
	move(dtime, env, pos_max_d, NULL);
}

void LocalPlayer::applyControl(float dtime)
{
	// Clear stuff
	swimming_vertical = false;

	setPitch(control.pitch);
	setYaw(control.yaw);

	// Nullify speed and don't run positioning code if the player is attached
	if(isAttached)
	{
		setSpeed(v3f(0,0,0));
		return;
	}

	v3f move_direction = v3f(0,0,1);
	move_direction.rotateXZBy(getYaw());

	v3f speedH = v3f(0,0,0); // Horizontal (X, Z)
	v3f speedV = v3f(0,0,0); // Vertical (Y)

	bool fly_allowed = m_gamedef->checkLocalPrivilege("fly");
	bool fast_allowed = m_gamedef->checkLocalPrivilege("fast");

	bool free_move = fly_allowed && g_settings->getBool("free_move");
	bool fast_move = fast_allowed && g_settings->getBool("fast_move");
	// When aux1_descends is enabled the fast key is used to go down, so fast isn't possible
	bool fast_climb = fast_move && control.aux1 && !g_settings->getBool("aux1_descends");
	bool continuous_forward = g_settings->getBool("continuous_forward");
	bool always_fly_fast = g_settings->getBool("always_fly_fast");

	// Whether superspeed mode is used or not
	bool superspeed = false;

	if (always_fly_fast && free_move && fast_move)
		superspeed = true;

	// Old descend control
	if(g_settings->getBool("aux1_descends"))
	{
		// If free movement and fast movement, always move fast
		if(free_move && fast_move)
			superspeed = true;

		// Auxiliary button 1 (E)
		if(control.aux1)
		{
			if(free_move)
			{
				// In free movement mode, aux1 descends
				if(fast_move)
					speedV.Y = -movement_speed_fast;
				else
					speedV.Y = -movement_speed_walk;
			}
			else if(in_liquid || in_liquid_stable)
			{
				speedV.Y = -movement_speed_walk;
				swimming_vertical = true;
			}
			else if(is_climbing)
			{
				speedV.Y = -movement_speed_climb;
			}
			else
			{
				// If not free movement but fast is allowed, aux1 is
				// "Turbo button"
				if(fast_move)
					superspeed = true;
			}
		}
	}
	// New minecraft-like descend control
	else
	{
		// Auxiliary button 1 (E)
		if(control.aux1)
		{
			if(!is_climbing)
			{
				// aux1 is "Turbo button"
				if(fast_move)
					superspeed = true;
			}
		}

		if(control.sneak)
		{
			if(free_move)
			{
				// In free movement mode, sneak descends
				if (fast_move && (control.aux1 || always_fly_fast))
					speedV.Y = -movement_speed_fast;
				else
					speedV.Y = -movement_speed_walk;
			}
			else if(in_liquid || in_liquid_stable)
			{
				if(fast_climb)
					speedV.Y = -movement_speed_fast;
				else
					speedV.Y = -movement_speed_walk;
				swimming_vertical = true;
			}
			else if(is_climbing)
			{
				if(fast_climb)
					speedV.Y = -movement_speed_fast;
				else
					speedV.Y = -movement_speed_climb;
			}
		}
	}

	if (continuous_forward)
		speedH += move_direction;

	if (control.up) {
		if (continuous_forward) {
			if (fast_move)
				superspeed = true;
		} else {
			speedH += move_direction;
		}
	}
	if (control.down) {
		speedH -= move_direction;
	}
	if (!control.up && !control.down) {
		speedH -= move_direction *
			(control.forw_move_joystick_axis / 32767.f);
	}
	if (control.left) {
		speedH += move_direction.crossProduct(v3f(0,1,0));
	}
	if (control.right) {
		speedH += move_direction.crossProduct(v3f(0,-1,0));
	}
	if (!control.left && !control.right) {
		speedH -= move_direction.crossProduct(v3f(0,1,0)) *
			(control.sidew_move_joystick_axis / 32767.f);
	}
	if(control.jump)
	{
		if (free_move) {
			if (g_settings->getBool("aux1_descends") || always_fly_fast) {
				if (fast_move)
					speedV.Y = movement_speed_fast;
				else
					speedV.Y = movement_speed_walk;
			} else {
				if(fast_move && control.aux1)
					speedV.Y = movement_speed_fast;
				else
					speedV.Y = movement_speed_walk;
			}
		}
		else if(m_can_jump)
		{
			/*
				NOTE: The d value in move() affects jump height by
				raising the height at which the jump speed is kept
				at its starting value
			*/
			v3f speedJ = getSpeed();
			if(speedJ.Y >= -0.5 * BS)
			{
				speedJ.Y = movement_speed_jump * physics_override_jump;
				setSpeed(speedJ);

				MtEvent *e = new SimpleTriggerEvent("PlayerJump");
				m_gamedef->event()->put(e);
			}
		}
		else if(in_liquid)
		{
			if(fast_climb)
				speedV.Y = movement_speed_fast;
			else
				speedV.Y = movement_speed_walk;
			swimming_vertical = true;
		}
		else if(is_climbing)
		{
			if(fast_climb)
				speedV.Y = movement_speed_fast;
			else
				speedV.Y = movement_speed_climb;
		}
	}

	// The speed of the player (Y is ignored)
	if(superspeed || (is_climbing && fast_climb) || ((in_liquid || in_liquid_stable) && fast_climb))
		speedH = speedH.normalize() * movement_speed_fast;
	else if(control.sneak && !free_move && !in_liquid && !in_liquid_stable)
		speedH = speedH.normalize() * movement_speed_crouch;
	else
		speedH = speedH.normalize() * movement_speed_walk;

	// Acceleration increase
	f32 incH = 0; // Horizontal (X, Z)
	f32 incV = 0; // Vertical (Y)
	if((!touching_ground && !free_move && !is_climbing && !in_liquid) || (!free_move && m_can_jump && control.jump))
	{
		// Jumping and falling
		if(superspeed || (fast_move && control.aux1))
			incH = movement_acceleration_fast * BS * dtime;
		else
			incH = movement_acceleration_air * BS * dtime;
		incV = 0; // No vertical acceleration in air
	}
	else if (superspeed || (is_climbing && fast_climb) || ((in_liquid || in_liquid_stable) && fast_climb))
		incH = incV = movement_acceleration_fast * BS * dtime;
	else
		incH = incV = movement_acceleration_default * BS * dtime;

	// Accelerate to target speed with maximum increment
	accelerateHorizontal(speedH * physics_override_speed, incH * physics_override_speed);
	accelerateVertical(speedV * physics_override_speed, incV * physics_override_speed);
}

v3s16 LocalPlayer::getStandingNodePos()
{
	if(m_sneak_node_exists)
		return m_sneak_node;
	return floatToInt(getPosition() - v3f(0, BS, 0), BS);
}

// Horizontal acceleration (X and Z), Y direction is ignored
void LocalPlayer::accelerateHorizontal(const v3f &target_speed, const f32 max_increase)
{
        if (max_increase == 0)
                return;

        v3f d_wanted = target_speed - m_speed;
        d_wanted.Y = 0;
        f32 dl = d_wanted.getLength();
        if (dl > max_increase)
                dl = max_increase;

        v3f d = d_wanted.normalize() * dl;

        m_speed.X += d.X;
        m_speed.Z += d.Z;
}

// Vertical acceleration (Y), X and Z directions are ignored
void LocalPlayer::accelerateVertical(const v3f &target_speed, const f32 max_increase)
{
        if (max_increase == 0)
                return;

        f32 d_wanted = target_speed.Y - m_speed.Y;
        if (d_wanted > max_increase)
                d_wanted = max_increase;
        else if (d_wanted < -max_increase)
                d_wanted = -max_increase;

        m_speed.Y += d_wanted;
}