Health Bars..

[Roose Bolton of the Dreadfort]

Hello SFML'ers!

I just wrote a solution for health bars in my game but not sure if its the best way/correct way to do it?

if it is, then maybe it could be useful for some people!

HealthBar.H

Code: [Select]

#pragma once

#include <SFML/Graphics.hpp>

class HealthBar
{
public:
HealthBar(void);
~HealthBar(void);

void Draw(sf::Vector2f iPosition, float currentHealth, float maxHealth);

sf::Sprite mCurrentHealth;
sf::Sprite mHealthBackground;
};

HealthBar.cpp

Code: [Select]

#include "HealthBar.h"
#include "GraphicsManager.h"

HealthBar::HealthBar(void)
{
//load from Graphics
this->mCurrentHealth.setTexture( *Graphics->GetTextureList()[2] );
this->mHealthBackground.setTexture( *Graphics->GetTextureList()[3] );

//Set initial sizes
this->mHealthBackground.setTextureRect( sf::Rect<int>(0, 0, 50, 5) );
this->mCurrentHealth.setTextureRect( sf::Rect<int>(0, 0, 50, 5) );
}


HealthBar::~HealthBar(void)
{
//TODO
}

void HealthBar::Draw(sf::Vector2f iPosition, float currentHealth, float maxHealth)
{
this->mCurrentHealth.setTextureRect( sf::Rect<int>(0, 0, currentHealth / 2, 5));
this->mHealthBackground.setTextureRect( sf::Rect<int>(0, 0, 50, 5) );

this->mCurrentHealth.setPosition(iPosition);
this->mHealthBackground.setPosition(iPosition);

//Draw background first!
Graphics->GetWindow().draw(mHealthBackground);
Graphics->GetWindow().draw(mCurrentHealth);
}

then in my GameEntities I instantiate a healthbar for them each.

each time the GameEntities draw function is called I then also call its healthbar to draw

Code: [Select]

bar.Draw(this->GetPosition() + sf::Vector2f(-22, -24), health, 100);

resulting in a nice health bar

[mateandmetal]

You are not using the float maxHealth in your Draw method?

sf::Rect<int> can be replaced with sf::IntRect

[Roose Bolton of the Dreadfort]

Not at the moment no :/ I will in the future 

is this the correct way 'as such' to do it? I get fair frame losses though when applying these healthbars to all my entities (50)

[mateandmetal]

Do you really need textures for your health bars?
I´m just drawing a simple sf::RectangleShape

If the entity has "low" health, I draw a red bar

cuad.setFillColor (sf::Color::Red);
 

else, I draw a green bar

cuad.setFillColor (sf::Color::Green);
 

[Roose Bolton of the Dreadfort]

I appear to get more FPS using textures :/

[thePyro_13]

You could try batching the health bars, draw them all at the same time so that opengl can reuse the stored texture.

Switching back to the health bar texture between every entity draw could be slowing it down a bit?