fieldanimation package reference

class fieldanimation.FieldAnimation(width, height, field, computeSahder=False, image=None)

Bases: object

Field Animation with OpenGL

1. draw the modulus of the vector field or a user defined image

   if requested;

2. set a framebuffer texture (screen texture) as the main

   rendering target:

   1. draw the background texture on the screen texture with a fixed opacity;

   2. decode the particles positions from the currentTracersPosition texture and draw them on the screen texture;

3. set the rendering target to the active window;

4. draw screen texture on the active window;

5. swap screen texture and background texture;

6. calculate the new particles positions

   (in the update shader) and encode them in the nextTracersPosition texture;

7. swap nextTracersPosition texture and

   currentTracersPosition texture;

__init__(width, height, field, computeSahder=False, image=None)

Animate 2D vector field

Parameters

• width (int) – width in pixels

• height (int) – height in pixels

• field (np.ndarray) – 2D vector field

• = True selects the compute shader version (cs) –

• = Optional background image (image) –

_initTracers()

Initialize the tracers positions

draw()

Render the OpenGL scene. This method is called automatically when the scene has to be rendered and is responsible for the animation.

drawImage()

Draw an image texture in background.

drawModulus(opacity)

Draw the modulus texture.

Parameters

opacity (float) – opacity (alpha) of the texture: 0 –> transparent 1 –> opaque

drawScreen()

Draw background texture and tracers on screen framebuffer texture

drawTexture(texture, opacity)

Draw texture on the screen.

Parameters

• ( (texture) – class:Texture): texture instance

• opacity (float) – opacity (alpha) of the texture 0 –> transparent 1 –> opaque

drawTracers()

Draw the tracers on the screen

resetRenderingTarget()

Bind first (default) framebuffer and reset the viewport.

setField(field)

Set the 2D vector field. Must be called every time a new vetor field is selected.

Parameters

field (np.ndarray) – 2D vector field

setRenderingTarget(texture)

Set texture as rendering target

Parameters

(class (texture) – texture instance): 2D vector field

setSize(width, height)

Set instance size. Must be called when the window is resized.

Parameters

• width (int) – window width in pixels

• height (int) – window height in pixels

property tracersCount

Return tracers count

Returns

number of tracers

updateTracers()

Update tracers position using the fragment shader provided by the graphic card for computing.

updateTracersCS()

Update tracers position using the compute shader provided by the graphic card for computing.

fieldanimation.field2RGB(field)

Return 2D field converted to uint8 RGB image (i.e. scaled in [0, 255])

Parameters

field (numpy.ndarray) – (u, v) 2D vector field instance

Returns

( rgb (numpy.ndarray): uint8 RGB image, uMin (float): u min, uMax (float): u max, vMin (float): v min, vMax (float): v max, ) (tuple): Return value

fieldanimation.glInfo()

Return OpenGL information dict WARNING: OpenGL context MUST be initialized !!!

Parameters

None –

Returns

OpenGL information dict

fieldanimation.modulus(field)

Return normalized modulus of 2D field image

Returns

normalized modulus of 2D field image (i.e. scaled in [0, 1.])

fieldanimation.shader

class fieldanimation.shader.Shader(path=None, **kargs)

Bases: object

Base shader class

__init__(path=None, **kargs)

Initialize self. See help(type(self)) for accurate signature.

_build_shader(sourceCode, shader_type)

Actual building of the shader

_link()

Link the program

addUniform(uniform, utype=None)

Add a uniform variable to the shader. If utype is not none it defines the setter function. Valid utypes are i, b, f, 2f, 4fv

addUniforms(uniformlist)

bind()

Bind the program, i.e. use it

delete()

setUniform(name, value)

setUniforms(nameandvalue)

unbind()

Unbind whatever program is currently bound - not necessarily this program, so this should probably be a class method instead.

fieldanimation.texture Module

class fieldanimation.texture.Texture(data=None, width=None, height=None, filt=GL_NEAREST, dtype=GL_UNSIGNED_BYTE)

Bases: object

__init__(data=None, width=None, height=None, filt=GL_NEAREST, dtype=GL_UNSIGNED_BYTE)

Texture object. If data is None an empty texture will be created

bind(texUnit=0)

handle()

unbind()

Subpackages

• fieldanimation.examples package
  • fieldanimation.examples.app