blueprints.assets module#

Note

It is recommended to not use assets directly. All property access is handeled through a front facing ThingType. Assets are UniqueThings.

class blueprints.assets.BaseAsset[source]#

Bases: AssetType, UniqueThing

Assets are used to link external resources to the model. Currently only MeshAssets,

HFieldAssets, TextureAssets, MaterialAssets are supported, but SkinAssets and

BoneAssets will be developed in a future version version.

property name: str#

The user specified name might potentially be altered to avoid a naming conflict by appending an enumeration scheme.

Return type:

str

class blueprints.assets.MaterialAsset[source]#

Bases: MaterialAssetType, BaseAsset, ColoredThing

See Material

Most attribute descriptions are partially taken from Mujoco.

__init__(texture=None, texrepeat=[1, 1], texuniform=False, emission=0.0, specular=0.5, shininess=0.5, reflectance=0.0, metallic=-1.0, roughness=-1.0, color=None, name=None)[source]#
Parameters:

  • texture (TextureType | None)

  • texrepeat (list[int | float] | ndarray)

  • texuniform (bool)

  • emission (int | float)

  • specular (int | float)

  • shininess (int | float)

  • reflectance (int | float)

  • metallic (int | float)

  • roughness (int | float)

  • color (str | object | None)

  • name (str | None)

property texrepeat: ndarray#

The number of repetitions of the Texture in two directions

Return type:

np.ndarray

property texuniform: bool#

For BoxTextures, this attribute controls how cube mapping is applied. The default value False means apply cube mapping directly, using the actual size of the object. The value “true” maps the texture to a unit object before scaling it to its actual size (geometric primitives are created by the renderer as unit objects and then scaled). In some cases this leads to more uniform texture appearance, but in general, which settings produces better results depends on the texture and the object. For 2d textures, this attribute interacts with texrepeat above. Let texrepeat be N. The default value “false” means that the 2d texture is repeated N times over the (z-facing side of the) object. The value “true” means that the 2D PlaneTexture is repeated N times over one spatial unit, regardless of object size.

Return type:

bool

property emission: float#

If set positive, the Material emitts lights.

Return type:

float

property specular: float#

Specularity in OpenGL. This value should be in the range [0 1].

Return type:

float

property shininess: float#

Shininess in OpenGL.

Return type:

float

property reflectance: float#

This attribute should be in the range [0 1]. If the value is greater than 0, and the material is applied to a plane or a box geom, the renderer will simulate reflectance. The larger the value, the stronger the reflectance. For boxes, only the face in the direction of the local +Z axis is reflective. Simulating reflectance properly requires ray-tracing which cannot (yet) be done in real-time. We are using the stencil buffer and suitable projections instead. Only the first reflective geom in the model is rendered as such. This adds one extra rendering pass through all geoms, in addition to the extra rendering pass added by each shadow-casting light.

Return type:

float

property metallic: float#

This attribute corresponds to uniform metallicity coefficient applied to the entire material. This attribute has no effect in MuJoCo’s native renderer, but it can be useful when rendering scenes with a physically-based renderer. In this case, if a non-negative value is specified, this metallic value should be multiplied by the metallic texture sampled value to obtain the final metallicity of the material.

Return type:

float

property roughness: float#

This attribute corresponds to uniform roughness coefficient applied to the entire material. This attribute has no effect in MuJoCo’s native renderer, but it can be useful when rendering scenes with a physically-based renderer. In this case, if a non-negative value is specified, this roughness value should be multiplied by the roughness texture sampled value to obtain the final roughness of the material.

Return type:

float

class blueprints.assets.TextureAsset[source]#

Bases: TextureAssetType, BaseAsset

See Texture

Most attribute descriptions are partially taken from Mujoco.

__init__(content=None, file=None, grid_size=[1, 1], grid_layout=None, fileright=None, fileleft=None, fileup=None, filedown=None, filefront=None, fileback=None, builtin=None, color_1=[0.8, 0.8, 0.8], color_2=[0.5, 0.5, 0.5], mark=None, color_mark=[0.0, 0.0, 0.0], random=0.01, width=0, height=0, h_flip=False, v_flip=False, n_channel=3, name=None)[source]#
Parameters:

  • content (str | None)

  • file (str | None)

  • grid_size (list[int])

  • grid_layout (str | None)

  • fileright (str | None)

  • fileleft (str | None)

  • fileup (str | None)

  • filedown (str | None)

  • filefront (str | None)

  • fileback (str | None)

  • builtin (str | None)

  • color_1 (object)

  • color_2 (object)

  • mark (str | None)

  • color_mark (object)

  • random (float)

  • width (int)

  • height (int)

  • h_flip (bool)

  • v_flip (bool)

  • n_channel (int)

  • name (str | None)

property type: str#

Derived type attribute for Mujoco,

Return type:

str

property content_type: str | None#

Content type (MIME type) taking values None, 'image/png', 'image/ktx' and 'image/vnd.mujoco.texture'.

Return type:

str | None

property gridsize: list[int]#

Grid size attrigute [n_rows, n_cols] defining the grid. For non-grid Textures this value is ignored.

Return type:

list[int]

property gridlayout: str | None#

The layout of the grid. See example above.

Return type:

str | None

property rgb1: ndarray#

The first color of a procedural Texture.

Return type:

blue.ColorType

property rgb2: ndarray#

The second color of a procedural Texture.

Return type:

blue.ColorType

property markrgb: ndarray#

The mark color of a procedural Texture.

Return type:

blue.ColorType

property hflip: bool#

If true, images loaded from file are flipped in the horizontal direction. Does not affect procedural textures.

Return type:

bool

property vflip: bool#

If true, images loaded from file are flipped in the vertical direction. Does not affect procedural textures.

Return type:

bool

property nchannel: int#

The number of channels in the texture image file. This allows loading 4-channel textures (RGBA) or single-channel textures (e.g., for Physics-Based Rendering properties such as roughness or metallic).

Return type:

int

property content: str | None#

Content type (MIME type) taking values None, 'image/png', 'image/ktx' and 'image/vnd.mujoco.texture'.

Return type:

str | None

property file: str | None#

Name of the texture file.

Return type:

str | None

property grid_size: list[int]#

Grid size attrigute [n_rows, n_cols] defining the grid. For non-grid Textures this value is ignored.

Return type:

list[int]

property grid_layout: str | None#

The layout of the grid. See example above.

Return type:

str | None

property fileright: str | None#

The file name for the right side of a Box.

Return type:

str | None

property fileleft: str | None#

The file name for the left side of a Box.

Return type:

str | None

property fileup: str | None#

The file name for the upper side of a Box.

Return type:

str | None

property filedown: str | None#

The file name for the down side of a Box.

Return type:

str | None

property filefront: str | None#

The file name for the front side of a Box.

Return type:

str | None

property fileback: str | None#

The file name for the back side of a Box.

Return type:

str | None

property builtin: str | None#

If set, this attribute specifies a builtin procedural Texture. See examples above.

Return type:

str | None

property color_1: Color#

The first color of a procedural Texture.

Return type:

blue.ColorType

property color_2: Color#

The second color of a procedural Texture.

Return type:

blue.ColorType

property mark: str | None#

If set this attribute specifies additional markings on a procedural Texture. Possible values are None, 'edge', 'cross' and 'random'. See examples above.

Return type:

str | None

property color_mark: Color#

The mark color of a procedural Texture.

Return type:

blue.ColorType

property random: float#

If the mark attribute is set to 'random', this attribute specifies the probability of a pixel in the texture being the mark_color.

Return type:

float

property width: int#

The width of a procedural texture, i.e., the number of columns in the image. Larger values usually result in higher quality images, although in some cases (e.g. checker patterns) small values are sufficient. For textures loaded from files, this attribute is ignored.

Return type:

int

property height: int#

The height of the procedural texture, i.e., the number of rows in the image. For Box and Skybox textures, this attribute is ignored and the height is set to 6 times the width. For textures loaded from files, this attribute is ignored.

Return type:

int

property n_channel: int#

The number of channels in the texture image file. This allows loading 4-channel textures (RGBA) or single-channel textures (e.g., for Physics-Based Rendering properties such as roughness or metallic).

Return type:

int

property h_flip: bool#

If true, images loaded from file are flipped in the horizontal direction. Does not affect procedural textures.

Return type:

bool

property v_flip: bool#

If true, images loaded from file are flipped in the vertical direction. Does not affect procedural textures.

Return type:

bool

class blueprints.assets.MeshAsset[source]#

Bases: MeshAssetType, BaseAsset, MoveableThing

MeshAssets handle access to the data attributes used to define the Mesh. All vertex, face, normals and texture coordinate data are stored in the MeshAssets MeshCache in the cache attribute.

In general, all Mesh data that are structured for xml representation and insufficient for user manipulation are named as singular vertex, face, texcoord and normal while their plural form vertecies, faces, cache.texcoords and cache.normals are used for user interpretable representations and manipulation.

Note

The position of MeshAssets is defined in mujoco via the refpos attribute, which differs to the standard pos attribute in that it defines the reference frames relative position w.r.t. to its position instead of the vice versa the relative position w.r.t. the reference frames origin, effectively making refpos = - pos. We find this to be unnecessarily confusing and opted to implement the standard position attribute only translating when the kinematic tree gets converted to Mujoco xml. It is highly recommended to use the pos argument to modify the MeshAssets position.

built#

A flag indicating whether the MeshAssets has been built. This is necessary since multiple Meshes might use the same MeshAsset in which case it should be built only once.

Type:

bool

cache#

The MeshCache which stores the Meshs data.

Type:

blue.CacheType

filename#

The filename from which the Mesh data is loaded or to which it will be saved.

Type:

str

xml_data#

A flag indicating whether the Mesh data is written into the xml directly or into and external file which is then linked to in the xml asset element.

Type:

bool

__init__(pos=[0.0, 0.0, 0.0], vertecies=None, faces=None, scale=[1.0, 1.0, 1.0], filename=None, centered=False, xml_data=False, cache=None, name=None, **kwargs)[source]#
Parameters:

  • pos (np.ndarray | list[int | float], optional) – pos : np.ndarray | list[int | float], optional Represents the position of the Asset. Changing this attribute also changes the properties x, y and z.

  • vertecies (np.ndarray | list[np.ndarray | list[float | int]] | None, optional) – A list of all vertex positions. The vertecies are stored in cache.

  • faces (list[np.ndarray | list[float | int]] | None, optional) – A list of all faces. A face consists of at least 3 indecies of vertecies. The faces are stored in cache.

  • scale (np.ndarray | list[int | float], optional) – The scale is a 1D array like object of length 3. Each component is used to scale the X, Y and Z-axis respectively. Changing the scale is computationally cheap since it does not change the vertecies or other data in cache.

  • filename (str | None, optional) – The filename from which the mesh data is loaded and to to which the mesh will be saved. The file is saved in a special directory such that no input file is overwritten by the output file.

  • centered (bool, optional) – If True the vertecies are normalized such that their mean position is the reference frames origin.

  • xml_data (bool, optional) – If True the Mesh data is not written to an external file and linked to in the xml, but written into the xml directly. It is recommended to only use this option if the Mesh data is small enough to not blot the xml.

  • cache (blue.ThingType | None, optional) – The Cache which stores the Mesh data.

  • name (str | None, optional) – The user specified name might potentially be altered to avoid a naming conflict by appending an enumeration scheme.

  • **kwargs – Keyword arguments are passed to super().__init__.

Return type:

None

load(filename)[source]#

This methods loads the mesh data from the filename to the assets cache.

Parameters:

filename (str) – The filename must be binary or ascii for OBJ files or binary for STL files.

Return type:

None

save(filename)[source]#

This method saves the mesh data from the cache to the filename.

Parameters:

filename (str) – The filename must either end with the '.obj or '.stl' file extension. Both file formats are saved as binary files.

Return type:

None

property file: str | None#

Derived dummy variable for Mujoco XML

Return type:

str

property filename: str | None#

The filename of the Mesh

Return type:

str

property refpos: ndarray#

The negative pos. This attribute is implemented for mujoco, but synchronized with pos which is recommended to to be used instead.

Return type:

np.ndarray

property vertex: ndarray#

This attribute is used to write construct the mujoco xml. It returns a flattened list of coordinates that is written raw to xml. For a structured list of vertecies see vertecies.

Return type:

np.ndarray

property face: ndarray | None#

This attribute is used to write to xml. It returns a flattened list of indecies that is written raw to xml. For a structured list of faces see faces.

Return type:

np.ndarray | None

property texcoord: ndarray | None#

This attribute is used to write to xml. It returns a flattened list of texture coordinates that is written raw to xml. For a structured list of texture coordinates see texcoords.

Return type:

np.ndarray | None

property normal: ndarray | None#

This attribute is used to write to xml. It returns a flattened list of face normals that is written raw to xml. For a structured list of face normals see normals.

Return type:

np.ndarray | None

property size: ndarray#

The size attribute specifies the ranges for each axis that the Mesh occupies.

Return type:

np.ndarray

property scale: ndarray#

The scale is a 1D array like object of length 3. Each component is used to scale the X, Y and Z-axis respectively. Changing the scale is computationally cheap since it does not change the vertecies or other data in cache.

Return type:

np.ndarray

property vertecies: list[ndarray]#

The list of vertecies. Each vertex is a np.ndarray with 3 components for each of the spatial dimensions.

Return type:

list[np.ndarray]

property faces: list[ndarray] | None#

The list of faces. Each face is a np.ndarray with n indecies for each of the vertecies of the face.

Return type:

list[np.ndarray] | None

class blueprints.assets.HFieldAsset[source]#

Bases: HFieldAssetType, BaseAsset, MoveableThing

See HField

Most attribute descriptions are partially taken from Mujoco.

__init__(filename=None, pos=[0.0, 0.0, 0.0], terrain=None, x_length=1, y_length=1, z_length=1, height_offset=1, xml_data=False, cache=None, name=None, **kwargs)[source]#
Parameters:

  • filename (str | None)

  • pos (ndarray | list[int | float])

  • terrain (ndarray | list[int | float] | None)

  • x_length (int | float | None)

  • y_length (int | float | None)

  • z_length (int | float | None)

  • height_offset (int | float | None)

  • xml_data (bool)

  • cache (ThingType | None)

  • name (str | None)

Return type:

None

property size: ndarray#

Derived size attribute for Mujoco XML.

Return type:

np.ndarray

property name: str#

The user specified name might potentially be altered to avoid a naming conflict by appending an enumeration scheme.

Return type:

str

property x_length#

Length along the X-axis of the HField.

Return type:

float

property y_length#

Length along the Y-axis of the HField.

Return type:

float

property z_length#

Length along the Z-axis of the HField.

Return type:

float

property height_offset#

Height offset along the Z-axis of the HField.

Return type:

float

property terrain: list[ndarray]#

The terrain data of the HField

Return type:

list[np.ndarray]