/// <summary>Adds the given texture to the atlas if it's not already on it,
/// taking up a set amount of space on the atlas.</summary>
/// <param name="texture">The texture to add.</param>
/// <param name="width">The x amount of space to take up on the atlas.</param>
/// <param name="height">The y amount of space to take up on the atlas.</param>
/// <returns>The location of the texture on the atlas.</returns>
internal AtlasLocation Add(AtlasEntity texture,int entityID,int width,int height){
// Pad width/height:
int spacedWidth=width+RawSpacing;
int spacedHeight=height+RawSpacing;
// Look for a spot to park this texture in the set of empty blocks.
// The aim is to make it fit in the smallest empty block possible to save space.
// This is done with a 'fitFactor' - this is simply the difference between the blocks area and the textures area.
// We want this value to be as small as possible.
int fitFactor=0;
AtlasLocation currentAccepted=null;
int area=spacedWidth*spacedHeight;
AtlasLocation currentEmpty=FirstEmpty;
while(currentEmpty!=null){
int factor=currentEmpty.FitFactor(spacedWidth,spacedHeight,area);
if(factor==0){
// Perfect fit - break right now; can't beat that!
currentAccepted=currentEmpty;
break;
}else if(factor!=-1){
// We can possibly fit here - is it the current smallest?
if(currentAccepted==null||factor<fitFactor){
// Yep! select it.
fitFactor=factor;
currentAccepted=currentEmpty;
}
}
currentEmpty=currentEmpty.EmptyAfter;
}
if(Mode==AtlasingMode.Columns && currentAccepted==null){
// Is there any more column space?
int max=ColumnProgress + spacedWidth;
if(max<=Dimension){
// Yep! Create a location using the remaining space:
currentAccepted=new AtlasLocation(this,ColumnProgress,0,Dimension-ColumnProgress,Dimension);
// As it's a new location, it's empty by default:
// (Note that it must be in the empty set, otherwise Select will throw the empty set entirely)
currentAccepted.AddToEmptySet();
}
}
if(currentAccepted==null){
// No space in this atlas to fit it in. Stop there.
if(CanOptimize){
// Request an optimise:
OptimizeRequested=true;
Stack.OptimizeRequested=true;
}
return null;
}
Stack.ActiveImages[entityID]=currentAccepted;
// And burn in the texture to the location (nb: it internally also writes the pixels to the atlas).
currentAccepted.Select(texture,width,height,RawSpacing);
return currentAccepted;
}
/// <summary>This texture has selected this location to fit into. This adds it to the atlas.</summary>
/// <param name="texture">The texture that wants to go here.</param>
/// <param name="width">The width of the texture in pixels.</param>
/// <param name="height">The height of the texture in pixels.</param>
public void Select(AtlasEntity image,int width,int height,int spacing){
// The given texture wants to go in this location.
// Width and height are given for dynamic textures - textures who's pixels are actually written straight to the atlas.
Empty=false;
int spacedWidth=width+spacing;
int spacedHeight=height+spacing;
// Remove from empty queue:
if(EmptyBefore==null){
Atlas.FirstEmpty=EmptyAfter;
}else{
EmptyBefore.EmptyAfter=EmptyAfter;
}
if(EmptyAfter==null){
Atlas.LastEmpty=EmptyBefore;
}else{
EmptyAfter.EmptyBefore=EmptyBefore;
}
int entityID=image.GetAtlasID();
if(AtlasID==entityID){
// This is a restore - we don't need to do anything else.
return;
}
Image=image;
AtlasID=entityID;
// If it's not a perfect fit, generate new atlas locations to the right and above of this one.
if(Atlas.Mode==AtlasingMode.SmallestSpace){
if(Width>spacedWidth){
// The textures a little thin.
// Generate a new area to the right of this one (NB: 0,0 is bottom left)
AtlasLocation newRight=new AtlasLocation(Atlas,X+spacedWidth,Y,Width-spacedWidth,height);
// Immediately mark this as empty:
newRight.AddToEmptySet();
}
if(Height>spacedHeight){
// The textures a little short.
// Generate a new area above this one (NB: 0,0 is bottom left)
AtlasLocation newTop=new AtlasLocation(Atlas,X,Y+spacedHeight,Width,Height-spacedHeight);
// Immediately mark this as empty:
newTop.AddToEmptySet();
}
}else{
int maxX=X+spacedWidth;
if(Atlas.ColumnProgress < maxX){
Atlas.ColumnProgress=maxX;
}
if(Height>spacedHeight){
// The textures a little short.
// Generate a new area above this one (NB: 0,0 is bottom left)
AtlasLocation newTop=new AtlasLocation(Atlas,X,Y+spacedHeight,Width,Height-spacedHeight);
// Immediately mark this as empty:
newTop.AddToEmptySet();
}
}
// Set the new size of this location for UV baking:
Width=width;
Height=height;
Spacing=spacing;
// Update the UV's:
BakeUV();
// Make sure the area is up to date:
Area=spacedWidth*spacedHeight;
// Write it in:
Flush();
}
/// <summary>Require the given image on any atlas. Note that this may reject the requirement if the image is too big and isn't worthwhile on an atlas.</summary>
public AtlasLocation RequireImage(AtlasEntity image){
int entityID=image.GetAtlasID();
AtlasLocation result;
if(ActiveImages.TryGetValue(entityID,out result)){
// Most calls fall through here.
return result;
}
int width;
int height;
image.GetDimensionsOnAtlas(out width,out height);
if(width>InitialSize || height>InitialSize){
// Won't fit or is unsuitable for atlasing anyway.
return null;
}
if(Last==null){
Create();
}else{
// Fast check - was this texture recently removed from any atlas?
// We might have the chance of restoring it.
// Their added at the back of the empty queue, so naturally, start at the end of the empty set
// and go back until we hit one with a null texture.
TextureAtlas currentAtlas=Last;
while(currentAtlas!=null){
AtlasLocation currentE=currentAtlas.LastEmpty;
while(currentE!=null){
if(currentE.Image==null){
// Nope! Shame.
break;
}else if(currentE.AtlasID==entityID){
// Ace! Time to bring it back from the dead.
currentE.Select(image,width,height,Spacing);
ActiveImages[entityID]=currentE;
return currentE;
}
currentE=currentE.EmptyBefore;
}
currentAtlas=currentAtlas.Previous;
}
}
// Push to top of stack:
result=Last.Add(image,entityID,width,height);
if(result!=null){
return result;
}
// Non-fitter - try fitting in lower stack frames:
TextureAtlas current=Last.Previous;
while(current!=null){
result=current.Add(image,entityID,width,height);
if(result!=null){
return result;
}
current=current.Previous;
}
// Still not fitting! Create a new stack frame:
Create();
return Last.Add(image,entityID,width,height);
}
//--------------------------------------
/// <summary>Removes a texture from the atlas.</summary>
/// <param name="texture">The texture to remove.</param>
public void Remove(AtlasEntity texture){
if(texture==null){
return;
}
AtlasLocation location=Get(texture.GetAtlasID());
if(location==null){
return;
}
// Make the location available:
location.Deselect();
}
