OpenGLDemo

OpenGLDemo

OpenGLDemo is probably the simplest possible demonstration of using OpenGL from a PyObjC application. It is a port of Apple’s “CocoaGL” example. Note that this requires PyOpenGL to be installed.

See: /Developer/Examples/OpenGL/Cocoa/CocoaGL
http://pyopengl.sourceforge.net/

The source of this application demonstrates - Using PyOpenGL from Cocoa

Bob Ippolito bob@redivi.com

Sources

OpenGLDemo.py

"""OpenGLDemo.py -- A simple demo of using OpenGL with Cocoa

To build the demo program, run this line in Terminal.app:

    $ python setup.py py2app -A

This creates a directory "dist" containing OpenGLDemo.app. (The
-A option causes the files to be symlinked to the .app bundle instead
of copied. This means you don't have to rebuild the app if you edit the
sources or nibs.)

This example requires PyOpenGL
"""

from Cocoa import *
from OpenGL.GL import *
from PyObjCTools import AppHelper


ClearColors = redIndex, greenIndex, blueIndex, alphaIndex = range(4)

class OpenGLDemoView(NSOpenGLView):

    def awakeFromNib(self):
        self.color_index = alphaIndex

    def initWithFrame_(self, frame):
        attribs = [
            NSOpenGLPFANoRecovery,
            NSOpenGLPFAWindow,
            NSOpenGLPFAAccelerated,
            NSOpenGLPFADoubleBuffer,
            NSOpenGLPFAColorSize, 24,
            NSOpenGLPFAAlphaSize, 8,
            NSOpenGLPFADepthSize, 24,
            NSOpenGLPFAStencilSize, 8,
            NSOpenGLPFAAccumSize, 0,
        ]
        fmt = NSOpenGLPixelFormat.alloc().initWithAttributes_(attribs)
        self = super(OpenGLDemoView, self).initWithFrame_pixelFormat_(frame, fmt)
        return self

    @objc.IBAction
    def setClearColor_(self, sender):
        self.color_index = sender.tag()
        self.setNeedsDisplay_(True)

    def drawRect_(self, pos, siz):
        x, y = pos
        w, h = siz
        glViewport(0, 0, w, h)
        clear_color = [0.0]*4
        clear_color[self.color_index] = 1.0
        glClearColor(*clear_color)
        glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT|GL_STENCIL_BUFFER_BIT)
        self.openGLContext().flushBuffer()

if __name__ == "__main__":
    AppHelper.runEventLoop()

setup.py

"""
Script for building the example.

Usage:
    python3 setup.py py2app
"""
from setuptools import setup

plist = dict(NSMainNibFile="OpenGLDemo")
setup(
    name="OpenGLDemo",
    app=["OpenGLDemo.py"],
    data_files=["OpenGLDemo.nib"],
    options=dict(py2app=dict(plist=plist)),
    setup_requires=[
        "py2app",
        "PyOpenGL",
        "pyobjc-framework-Cocoa",
    ]
)

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