direct.showbase.Loader

from direct.showbase.Loader import Loader

This module contains a high-level interface for loading models, textures, sound, music, shaders and fonts from disk.

Inheritance diagram

Inheritance diagram of direct.showbase.Loader

class Loader(base)[source]

Bases: DirectObject

Load models, textures, sounds, and code.

__init__(self, base)[source]
asyncFlattenStrong(self, model, inPlace=True, callback=None, extraArgs=[])[source]

Performs a model.flattenStrong() operation in a sub-thread (if threading is compiled into Panda). The model may be a single NodePath, or it may be a list of NodePaths.

Each model is duplicated and flattened in the sub-thread.

If inPlace is True, then when the flatten operation completes, the newly flattened copies are automatically dropped into the scene graph, in place the original models.

If a callback is specified, then it is called after the operation is finished, receiving the flattened model (or a list of flattened models).

cancelRequest(self, cb)[source]

Cancels an aysynchronous loading or flatten request issued earlier. The callback associated with the request will not be called after cancelRequest() has been performed.

This is now deprecated: call cb.cancel() instead.

destroy(self)[source]
isRequestPending(self, cb)[source]

Returns true if an asynchronous loading or flatten request issued earlier is still pending, or false if it has completed or been cancelled.

This is now deprecated: call cb.done() instead.

load2DTextureArray(self, texturePattern, readMipmaps=False, okMissing=False, minfilter=None, magfilter=None, anisotropicDegree=None, loaderOptions=None, multiview=None, numViews=2)[source]

texturePattern is a string that contains a sequence of one or more hash characters (‘#’), which will be filled in with the z-height number. Returns a 2-D Texture array object, suitable for rendering array of textures.

okMissing should be True to indicate the method should return None if the texture file is not found. If it is False, the method will raise an exception if the texture file is not found or cannot be loaded.

If readMipmaps is True, then the filename string must contain two sequences of hash characters; the first group is filled in with the z-height number, and the second group with the mipmap index number.

If multiview is true, it indicates to load a multiview or stereo texture. In this case, numViews should also be specified (the default is 2), and the sequence of texture images will be divided into numViews views. The total z-height will be (numImages / numViews). For instance, if you read 16 images with numViews = 2, then you have created a stereo multiview image, with z = 8. In this example, images numbered 0 - 7 will be part of the left eye view, and images numbered 8 - 15 will be part of the right eye view.

load3DTexture(self, texturePattern, readMipmaps=False, okMissing=False, minfilter=None, magfilter=None, anisotropicDegree=None, loaderOptions=None, multiview=None, numViews=2)[source]

texturePattern is a string that contains a sequence of one or more hash characters (‘#’), which will be filled in with the z-height number. Returns a 3-D Texture object, suitable for rendering volumetric textures.

okMissing should be True to indicate the method should return None if the texture file is not found. If it is False, the method will raise an exception if the texture file is not found or cannot be loaded.

If readMipmaps is True, then the filename string must contain two sequences of hash characters; the first group is filled in with the z-height number, and the second group with the mipmap index number.

If multiview is true, it indicates to load a multiview or stereo texture. In this case, numViews should also be specified (the default is 2), and the sequence of texture images will be divided into numViews views. The total z-height will be (numImages / numViews). For instance, if you read 16 images with numViews = 2, then you have created a stereo multiview image, with z = 8. In this example, images numbered 0 - 7 will be part of the left eye view, and images numbered 8 - 15 will be part of the right eye view.

loadCubeMap(self, texturePattern, readMipmaps=False, okMissing=False, minfilter=None, magfilter=None, anisotropicDegree=None, loaderOptions=None, multiview=None)[source]

texturePattern is a string that contains a sequence of one or more hash characters (‘#’), which will be filled in with the face index number (0 through 6). Returns a six-face cube map Texture object.

okMissing should be True to indicate the method should return None if the texture file is not found. If it is False, the method will raise an exception if the texture file is not found or cannot be loaded.

If readMipmaps is True, then the filename string must contain two sequences of hash characters; the first group is filled in with the face index number, and the second group with the mipmap index number.

If multiview is true, it indicates to load a multiview or stereo cube map. For a stereo cube map, 12 images will be loaded–images numbered 0 - 5 will become the left eye view, and images 6 - 11 will become the right eye view. In general, the number of images found on disk must be a multiple of six, and each six images will define a new view.

loadFont(self, modelPath, spaceAdvance=None, lineHeight=None, pointSize=None, pixelsPerUnit=None, scaleFactor=None, textureMargin=None, polyMargin=None, minFilter=None, magFilter=None, anisotropicDegree=None, color=None, outlineWidth=None, outlineFeather=0.1, outlineColor=LVecBase4f(0, 0, 0, 1), renderMode=None, okMissing=False)[source]

modelPath is a string.

This loads a special model as a TextFont object, for rendering text with a TextNode. A font file must be either a special egg file (or bam file) generated with egg-mkfont, which is considered a static font, or a standard font file (like a TTF file) that is supported by FreeType, which is considered a dynamic font.

okMissing should be True to indicate the method should return None if the font file is not found. If it is False, the method will raise an exception if the font file is not found or cannot be loaded.

Most font-customization parameters accepted by this method (except lineHeight and spaceAdvance) may only be specified for dynamic font files like TTF files, not for static egg files.

lineHeight specifies the vertical distance between consecutive lines, in Panda units. If unspecified, it is taken from the font information. This parameter may be specified for static as well as dynamic fonts.

spaceAdvance specifies the width of a space character (ascii 32), in Panda units. If unspecified, it is taken from the font information. This may be specified for static as well as dynamic fonts.

The remaining parameters may only be specified for dynamic fonts.

pixelsPerUnit controls the visual quality of the rendered text characters. It specifies the number of texture pixels per each Panda unit of character height. Increasing this number increases the amount of detail that can be represented in the characters, at the expense of texture memory.

scaleFactor also controls the visual quality of the rendered text characters. It is the amount by which the characters are rendered bigger out of Freetype, and then downscaled to fit within the texture. Increasing this number may reduce some artifacts of very small font characters, at a small cost of processing time to generate the characters initially.

textureMargin specifies the number of pixels of the texture to leave between adjacent characters. It may be a floating-point number. This helps reduce bleed-through from nearby characters within the texture space. Increasing this number reduces artifacts at the edges of the character cells (especially for very small text scales), at the expense of texture memory.

polyMargin specifies the amount of additional buffer to create in the polygon that represents each character, in Panda units. It is similar to textureMargin, but it controls the polygon buffer, not the texture buffer. Increasing this number reduces artifacts from letters getting chopped off at the edges (especially for very small text scales), with some increasing risk of adjacent letters overlapping and obscuring each other.

minFilter, magFilter, and anisotropicDegree specify the texture filter modes that should be applied to the textures that are created to hold the font characters.

If color is not None, it should be a VBase4 specifying the foreground color of the font. Specifying this option breaks TextNode.setColor(), so you almost never want to use this option; the default (white) is the most appropriate for a font, as it allows text to have any arbitrary color assigned at generation time. However, if you want to use a colored outline (below) with a different color for the interior, for instance a yellow letter with a blue outline, then you need this option, and then all text generated with this font will have to be yellow and blue.

If outlineWidth is nonzero, an outline will be created at runtime for the letters, and outlineWidth will be the desired width of the outline, in points (most fonts are 10 points high, so 0.5 is often a good choice). If you specify outlineWidth, you can also specify outlineFeather (0.0 .. 1.0) and outlineColor. You may need to increase pixelsPerUnit to get the best results.

if renderMode is not None, it may be one of the following symbols to specify a geometry-based font:

TextFont.RMTexture - this is the default. Font characters

are rendered into a texture and applied to a polygon. This gives the best general-purpose results.

TextFont.RMWireframe - Font characters are rendered as a

sequence of one-pixel lines. Consider enabling line or multisample antialiasing for best results.

TextFont.RMPolygon - Font characters are rendered as a

flat polygon. This works best for very large characters, and generally requires polygon or multisample antialiasing to be enabled for best results.

TextFont.RMExtruded - Font characters are rendered with a

3-D outline made of polygons, like a cookie cutter. This is appropriate for a 3-D scene, but may be completely invisible when assigned to a 2-D scene and viewed normally from the front, since polygons are infinitely thin.

TextFont.RMSolid - A combination of RMPolygon and

RMExtruded: a flat polygon in front with a solid three-dimensional edge. This is best for letters that will be tumbling in 3-D space.

If the texture mode is other than RMTexture, most of the above parameters do not apply, though pixelsPerUnit still does apply and roughly controls the tightness of the curve approximation (and the number of vertices generated).

loadModel(self, modelPath, loaderOptions=None, noCache=None, allowInstance=False, okMissing=None, callback=None, extraArgs=[], priority=None, blocking=None)[source]

Attempts to load a model or models from one or more relative pathnames. If the input modelPath is a string (a single model pathname), the return value will be a NodePath to the model loaded if the load was successful, or None otherwise. If the input modelPath is a list of pathnames, the return value will be a list of NodePath objects and/or Nones.

loaderOptions may optionally be passed in to control details about the way the model is searched and loaded. See the LoaderOptions class for more.

The default is to look in the ModelPool (RAM) cache first, and return a copy from that if the model can be found there. If the bam cache is enabled (via the model-cache-dir config variable), then that will be consulted next, and if both caches fail, the file will be loaded from disk. If noCache is True, then neither cache will be consulted or updated.

If allowInstance is True, a shared instance may be returned from the ModelPool. This is dangerous, since it is easy to accidentally modify the shared instance, and invalidate future load attempts of the same model. Normally, you should leave allowInstance set to False, which will always return a unique copy.

If okMissing is True, None is returned if the model is not found or cannot be read, and no error message is printed. Otherwise, an IOError is raised if the model is not found or cannot be read (similar to attempting to open a nonexistent file). (If modelPath is a list of filenames, then IOError is raised if any of the models could not be loaded.)

If callback is not None, then the model load will be performed asynchronously. In this case, loadModel() will initiate a background load and return immediately. The return value will be an object that can be used to check the status, cancel the request, or use it in an await expression. Unless callback is the special value True, when the requested model(s) have finished loading, it will be invoked with the n loaded models passed as its parameter list. It is possible that the callback will be invoked immediately, even before loadModel() returns. If you use callback, you may also specify a priority, which specifies the relative importance over this model over all of the other asynchronous load requests (higher numbers are loaded first).

True asynchronous model loading requires Panda to have been compiled with threading support enabled (you can test Thread.isThreadingSupported()). In the absence of threading support, the asynchronous interface still exists and still behaves exactly as described, except that loadModel() might not return immediately.

loadModelCopy(self, string)[source]

NOTE: This method is deprecated and should not be used. Attempt to load a model from modelPool, if not present then attempt to load it from disk. Return a nodepath to a copy of the model if successful or None otherwise

loadModelNode(self, modelPath)[source]

modelPath is a string.

This is like loadModelOnce in that it loads a model from the modelPool, but it does not then instance it to hidden and it returns a Node instead of a NodePath. This is particularly useful for special models like fonts that you don’t care about where they’re parented to, and you don’t want a NodePath anyway–it prevents accumulation of instances of the font model under hidden.

However, if you’re loading a font, see loadFont(), below.

loadModelOnce(self, modelPath)[source]

modelPath is a string.

Attempt to load a model from modelPool, if not present then attempt to load it from disk. Return a nodepath to the model if successful or None otherwise

loadMusic(self, *args, **kw)[source]

Loads one or more sound files, specifically designated as a “music” file (that is, uses the musicManager to load the sound). There is no distinction between sound effect files and music files other than the particular AudioManager used to load the sound file, but this distinction allows the sound effects and/or the music files to be adjusted as a group, independently of the other group.

loadSfx(self, *args, **kw)[source]

Loads one or more sound files, specifically designated as a “sound effect” file (that is, uses the sfxManager to load the sound). There is no distinction between sound effect files and music files other than the particular AudioManager used to load the sound file, but this distinction allows the sound effects and/or the music files to be adjusted as a group, independently of the other group.

loadShader(self, shaderPath, okMissing=False)[source]
loadSound(self, manager, soundPath, positional=False, callback=None, extraArgs=[])[source]

Loads one or more sound files, specifying the particular AudioManager that should be used to load them. The soundPath may be either a single filename, or a list of filenames. If a callback is specified, the loading happens in the background, just as in loadModel(); otherwise, the loading happens before loadSound() returns.

loadTexture(self, texturePath, alphaPath=None, readMipmaps=False, okMissing=False, minfilter=None, magfilter=None, anisotropicDegree=None, loaderOptions=None, multiview=None)[source]

texturePath is a string.

Attempt to load a texture from the given file path using TexturePool class. Returns a Texture object, or raises IOError if the file could not be loaded.

okMissing should be True to indicate the method should return None if the texture file is not found. If it is False, the method will raise an exception if the texture file is not found or cannot be loaded.

If alphaPath is not None, it is the name of a grayscale image that is applied as the texture’s alpha channel.

If readMipmaps is True, then the filename string must contain a sequence of hash characters (‘#’) that are filled in with the mipmap index number, and n images will be loaded individually which define the n mipmap levels of the texture. The base level is mipmap level 0, and this defines the size of the texture and the number of expected mipmap images.

If minfilter or magfilter is not None, they should be a symbol like SamplerState.FTLinear or SamplerState.FTNearest. (minfilter may be further one of the Mipmap filter type symbols.) These specify the filter mode that will automatically be applied to the texture when it is loaded. Note that this setting may override the texture’s existing settings, even if it has already been loaded. See egg-texture-cards for a more robust way to apply per-texture filter types and settings.

If anisotropicDegree is not None, it specifies the anisotropic degree to apply to the texture when it is loaded. Like minfilter and magfilter, egg-texture-cards may be a more robust way to apply this setting.

If multiview is true, it indicates to load a multiview or stereo texture. In this case, the filename should contain a hash character (‘#’) that will be replaced with ‘0’ for the left image and ‘1’ for the right image. Larger numbers are also allowed if you need more than two views.

loaderIndex = 0
notify = <direct.directnotify.Notifier.Notifier object>
saveModel(self, modelPath, node, loaderOptions=None, callback=None, extraArgs=[], priority=None, blocking=None)[source]

Saves the model (a NodePath or PandaNode) to the indicated filename path. Returns true on success, false on failure. If a callback is used, the model is saved asynchronously, and the true/false status is passed to the callback function.

unloadModel(self, model)[source]

model is the return value of loadModel(). For backward compatibility, it may also be the filename that was passed to loadModel(), though this requires a disk search.

unloadSfx(self, sfx)[source]
unloadShader(self, shaderPath)[source]
unloadTexture(self, texture)[source]

Removes the previously-loaded texture from the cache, so that when the last reference to it is gone, it will be released. This also means that the next time the same texture is loaded, it will be re-read from disk (and duplicated in texture memory if there are still outstanding references to it).

The texture parameter may be the return value of any previous call to loadTexture(), load3DTexture(), or loadCubeMap().