Here are two common/easy ways. One would be to rely on static getters or singleton instances. You can extend this however you see fit; e.g. storing your textures by a String identifier in a hash map.
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| MyEntity {
Texture texture;
public MyEntity() {
this.texture = MyResources.getInstance().getMyTexture();
}
} |
Another common solution is to pass the single texture to the entity when you create it:
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| MyEntity {
Texture texture;
public MyEntity(Texture texture) {
this.texture = texture;
}
} |
To draw a "sub image" of a texture (i.e. render a particular sprite in a sheet), you need to define your texcoords properly. With slick-util, you might define an Image2D/Sprite class that holds the normalized texture offsets and width/height that will be passed to glTexCoord2f:
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| public Image2D(Texture texture) {
this.texture = texture;
this.normalizedWidth = texture.getWidth();
this.normalizedHeight = texture.getHeight();
this.width = texture.getImageWidth();
this.height = texture.getImageHeight();
this.centerX = width / 2f;
this.centerY = height / 2f;
}
public Image2D getSubImage(float x, float y, float width, float height) {
float tx = ( x / this.width * normalizedWidth ) + textureOffsetX;
float ty = ( y / this.height * normalizedHeight ) + textureOffsetY;
float tw = width / this.width * normalizedWidth;
float th = height / this.height * normalizedHeight;
Image2D img = copy();
img.textureOffsetX = tx;
img.textureOffsetY = ty;
img.width = width;
img.height = height;
img.normalizedWidth = tw;
img.normalizedHeight = th;
img.centerX = width / 2f;
img.centerY = height / 2f;
return img;
} |
