GLUMPY¶

glumpy is a small python library for the rapid vizualization of numpy arrays, (mainly two dimensional) that has been designed with efficiency in mind. If you want to draw nice figures for inclusion in a scientific article, better use matplotlib. If you want to have a sense of whats going on in your simulation while it is running, then maybe glumpy can help you.

glumpy is made on top of PyOpenGL (http://pyopengl.sourceforge.net/)

glumpy.atb¶

Glumpy provides bindings and demos to use AntTweakBar http://anttweakbar.sourceforge.net/doc/

forks¶

https://github.com/davidcox/glumpy key binding extension

alternatives¶

installations¶

Delta¶

Into chroma virtualenv python (based on macports python 2.7.6):

glumpy-get
cd glumpy
python setup.py install
...
Writing /usr/local/env/chroma_env/lib/python2.7/site-packages/glumpy-0.2.1-py2.7.egg-info

G4PB¶

Into macports py26:

g4pb:~ blyth$ glumpy-
g4pb:~ blyth$ glumpy-get
Cloning into 'glumpy'...
remote: Counting objects: 1026, done.
Receiving objects: 100% (1026/1026), 4.26 MiB | 899 KiB/s, done.
Resolving deltas: 100% (699/699), done.
g4pb:glumpy blyth$ pwd
/usr/local/env/graphics/glumpy
g4pb:glumpy blyth$ cd glumpy/
g4pb:glumpy blyth$ which python
/opt/local/bin/python
g4pb:glumpy blyth$ sudo python setup.py install
...
Writing /opt/local/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/glumpy-0.2.1-py2.6.egg-info
g4pb:glumpy blyth$

issue1 : undefined function glutMainLoopEvent (OSX 10.5.8 macports py26)¶

Kludge fix via edit to backend_glut.py

Traceback (most recent call last):
  File "/Users/blyth/env/bin/daeviewgl.py", line 4, in <module>
    main()
  File "/opt/local/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/env/geant4/geometry/collada/daeview/daeviewgl.py", line 223, in main
    gp.show()
  File "/opt/local/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/glumpy/window/backend_glut.py", line 58, in show
    _window.start()
  File "/opt/local/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/glumpy/window/backend_glut.py", line 591, in start
    glut.glutMainLoopEvent()
  File "/opt/local/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/OpenGL/platform/baseplatform.py", line 340, in __call__
    self.__name__, self.__name__,
OpenGL.error.NullFunctionError: Attempt to call an undefined function glutMainLoopEvent, check for bool(glutMainLoopEvent) before calling
g4pb:~ blyth$

glumpy/window/backend_glut.py failing in start:

585         if not self._interactive:
586             #glut.glutMainLoop()
587             while not self._stop_mainloop:
588                 try:
589                     glut.glutCheckLoop()
590                 except:
591                     glut.glutMainLoopEvent()
592

Uncommenting the glut.glutMainLook() on line 586 succeeds to get graphical view to appear:

g4pb:~ blyth$ sudo vi /opt/local/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/glumpy/window/backend_glut.py +586

issue2 : key/trackpad binding (OSX 10.5.8 macports py26)¶

Unable to Z/XY pan (key binding/scroll wheel?)

issue3 : fig.save via FBO fails¶

My workaround is to avoid FBO and simply glReadPixels from the framebuffer:

12   File "/usr/local/env/chroma_env/lib/python2.7/site-packages/env/geant4/geometry/collada/daeview/daeinteractivityhandler.py", line 171, in save_to_file
13     self.fig.save("%s.png" % name )
14   File "/usr/local/env/chroma_env/lib/python2.7/site-packages/glumpy/figure.py", line 293, in save
15     fbo.glRenderbufferStorageEXT( fbo.GL_RENDERBUFFER_EXT, fbo.GL_DEPTH_COMPONENT, w, h)
16 AttributeError: 'module' object has no attribute 'GL_DEPTH_COMPONENT'

Attempted to fix on Delta by commenting depthbuffer, this succeeds to write a file, but checking in Preview its distinctly odd looking. Code changes remain:

(chroma_env)delta:glumpy blyth$ pwd
/usr/local/env/chroma_env/lib/python2.7/site-packages/glumpy
(chroma_env)delta:glumpy blyth$ vi figure.py

demos¶

obj-viewer¶

Nice trackball operation

/usr/local/env/graphics/glumpy/glumpy/demos/obj-viewer.py

interesting code¶

graphics/vertex_buffer.py¶

Attributes describe the meaning of VBO arrays.

Base class: VertexAttribute(count,gltype,stride,offset) with sub classes that check ctor arguments and provide enable methods eg:

VertexAttribute_color: gl.glColorPointer(self.count, self.gltype, self.stride, self.offset) gl.glEnableClientState(gl.GL_COLOR_ARRAY)
VertexAttribute_edge_flag: gl.glEdgeFlagPointer(self.stride, self.offset) gl.glEnableClientState(gl.GL_EDGE_FLAG_ARRAY)
VertexAttribute_fog_coord: gl.glFogCoordPointer(self.count, self.gltype, self.stride, self.offset) gl.glEnableClientState(gl.GL_FOG_COORD_ARRAY)
VertexAttribute_normal: gl.glNormalPointer(self.gltype, self.stride, self.offset) gl.glEnableClientState(gl.GL_NORMAL_ARRAY)
VertexAttribute_secondary_color: gl.glSecondaryColorPointer(3, self.gltype, self.stride, self.offset) gl.glEnableClientState(gl.GL_SECONDARY_COLOR_ARRAY)
VertexAttribute_tex_coord: gl.glTexCoordPointer(self.count, self.gltype, self.stride, self.offset) gl.glEnableClientState(gl.GL_TEXTURE_COORD_ARRAY)
VertexAttribute_position: gl.glVertexPointer(self.count, self.gltype, self.stride, self.offset) gl.glEnableClientState(gl.GL_VERTEX_ARRAY)
VertexAttribute_generic: gl.glVertexAttribPointer( self.index, self.count, self.gltype, self.normalized, self.stride, self.offset ); gl.glEnableVertexAttribArray( self.index )

gl***Pointer	GL_***_ARRAY	Att names
Color	COLOR	color	c
EdgeFlag	EDGE_FLAG	edge_flag	e
FogCoord	FOG_COORD	fog_coord	f
Normal	NORMAL	normal	n
SecondaryColor	SECONDARY_COLOR	secondary_color	s
TexCoord	TEXTURE_COORD	tex_coord	t
Vertex	VERTEX	position	p
VertexAttrib	N/A

clear pattern followed by all apart from _generic.
some pointer calls take not all of count/gltype/stride/offset

Buffer identifiers vertices_id and indices_id are generated and bound to GL_ARRAY_BUFFER and GL_ELEMENT_ARRAY_BUFFER and the buffer data is passed, causing once only upload to the GPU in the ctor.

self.vertices_id = gl.glGenBuffers(1)
gl.glBindBuffer( gl.GL_ARRAY_BUFFER, self.vertices_id )
gl.glBufferData( gl.GL_ARRAY_BUFFER, self.vertices, gl.GL_STATIC_DRAW )
gl.glBindBuffer( gl.GL_ARRAY_BUFFER, 0 )

self.indices_id = gl.glGenBuffers(1)
gl.glBindBuffer( gl.GL_ELEMENT_ARRAY_BUFFER, self.indices_id )
gl.glBufferData( gl.GL_ELEMENT_ARRAY_BUFFER, self.indices, gl.GL_STATIC_DRAW )
gl.glBindBuffer( gl.GL_ELEMENT_ARRAY_BUFFER, 0 )

Thence at VBO draw:

GL_ARRAY_BUFFER bound using vertices_id
GL_ELEMENT_ARRAY_BUFFER bound using indices_id
any generic attributes are enabled
attributes chosen by what argument first letters are enabled which switch the meanings of the array data
gl.glDrawElements( mode, self.indices.size, gl.gl_UNSIGNED_INT, None )
GL_ARRAY_BUFFER and GL_ELEMENT_ARRAY_BUFFER are unbound

def draw( self, mode=gl.GL_QUADS, what='pnctesf' ):
    gl.glPushClientAttrib( gl.GL_CLIENT_VERTEX_ARRAY_BIT )
    gl.glBindBuffer( gl.GL_ARRAY_BUFFER, self.vertices_id )
    gl.glBindBuffer( gl.GL_ELEMENT_ARRAY_BUFFER, self.indices_id )

    for attribute in self.generic_attributes:
        attribute.enable()

    for c in self.attributes.keys():
        if c in what:
            self.attributes[c].enable()
    gl.glDrawElements( mode, self.indices.size, gl.GL_UNSIGNED_INT, None)
    gl.glBindBuffer( gl.GL_ELEMENT_ARRAY_BUFFER, 0 )
    gl.glBindBuffer( gl.GL_ARRAY_BUFFER, 0 )
    gl.glPopClientAttrib( )

http://www.opengl.org/sdk/docs/man2/xhtml/glDrawElements.xml

glDrawElements( GLenum      mode,
                GLsizei     count,      # Specifies the number of elements to be rendered
                GLenum      type,       # Specifies the type of the values in indices.
                                          Must be one of GL_UNSIGNED_BYTE, GL_UNSIGNED_SHORT, or GL_UNSIGNED_INT.
                const GLvoid *indices); # Specifies a pointer to the location where the indices are stored

When glDrawElements is called, it uses count sequential elements from an enabled array, starting at indices to construct a sequence of geometric primitives. mode specifies what kind of primitives are constructed and how the array elements construct these primitives. If more than one array is enabled, each is used. If GL_VERTEX_ARRAY is not enabled, no geometric primitives are constructed.

mode
GL_POINTS
GL_LINE_STRIP
GL_LINE_LOOP
GL_LINES
GL_TRIANGLE_STRIP
GL_TRIANGLE_FAN
GL_TRIANGLES
GL_QUAD_STRIP
GL_QUADS
GL_POLYGON

http://www.opengl.org/sdk/docs/man2/xhtml/glDrawRangeElements.xml

void glDrawRangeElements(   GLenum      mode,
                            GLuint      start,
                            GLuint      end,
                            GLsizei     count,
                            GLenum      type,
                            const GLvoid *      indices);

glDrawRangeElements is available only if the GL version is 1.2 or greater.

glumpy timers¶

TODO: work out way to switch off timers

/usr/local/env/graphics/glumpy/glumpy/glumpy/window/backend_glut.py:

560     def start(self):
561         ''' Starts main loop. '''
562
563         # Start timers
564         for i in range(len(self._timer_stack)):
565             def func(index):
566                 handler, fps = self._timer_stack[index]
567                 t = glut.glutGet(glut.GLUT_ELAPSED_TIME)
568                 dt = (t - self._timer_date[index])/1000.0
569                 self._timer_date[index] = t
570                 handler(dt)
571                 glut.glutTimerFunc(int(1000./fps), func, index)
572                 self._timer_date[index] = glut.glutGet(glut.GLUT_ELAPSED_TIME)
573             fps = self._timer_stack[i][1]
574             glut.glutTimerFunc(int(1000./fps), func, i)

delta:glumpy blyth$ find . -name '*.py' -exec grep -H _timer {} \;
./graphics/vertex_buffer.py:def on_timer(value):
./graphics/vertex_buffer.py:    glut.glutTimerFunc(10, on_timer, 0)
./graphics/vertex_buffer.py:    glut.glutTimerFunc(10, on_timer, 0)
./window/backend_glut.py:        self._timer_stack = []
./window/backend_glut.py:        self._timer_date = []
./window/backend_glut.py:        for i in range(len(self._timer_stack)):
./window/backend_glut.py:                handler, fps = self._timer_stack[index]
./window/backend_glut.py:                dt = (t - self._timer_date[index])/1000.0
./window/backend_glut.py:                self._timer_date[index] = t
./window/backend_glut.py:                self._timer_date[index] = glut.glutGet(glut.GLUT_ELAPSED_TIME)
./window/backend_glut.py:            fps = self._timer_stack[i][1]
./window/window.py:            self._timer_stack.append((func, fps))
./window/window.py:            self._timer_date.append(0)
delta:glumpy blyth$

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GLUMPY¶

glumpy.atb¶

forks¶

alternatives¶

installations¶

Delta¶

G4PB¶

issue1 : undefined function glutMainLoopEvent (OSX 10.5.8 macports py26)¶

issue2 : key/trackpad binding (OSX 10.5.8 macports py26)¶

issue3 : fig.save via FBO fails¶

demos¶

obj-viewer¶

interesting code¶

graphics/vertex_buffer.py¶

glumpy timers¶

Navigation

Quick search

Links

Content Skeleton

This Page

Previous topic

Next topic

GLUMPY¶

glumpy.atb¶

forks¶

alternatives¶

installations¶

Delta¶

G4PB¶

issue1 : undefined function glutMainLoopEvent (OSX 10.5.8 macports py26)¶

issue2 : key/trackpad binding (OSX 10.5.8 macports py26)¶

issue3 : fig.save via FBO fails¶

demos¶

obj-viewer¶

interesting code¶

graphics/vertex_buffer.py¶

glumpy timers¶

Navigation