Here's a recent project I've been working on in python/C for games: http://code.google.com/p/py-lepton/source/browse/trunk/
Note there is nothing os x specific about it other than the location of some include and library directories in setup.py because it depends on the OpenGL C API. Everything else is vanilla distutils. -Casey On Thu, Nov 20, 2008 at 2:16 PM, Steve <[EMAIL PROTECTED]> wrote: > > > > On Nov 20, 3:13 pm, "Casey Duncan" <[EMAIL PROTECTED]> wrote: >> Here's one way you could do it: >> >> Grab a texture from the buffer that is the bounding box of your lasso >> selection. >> Make a lasso mask that is white only inside the selection >> draw the mask into the stencil buffer >> draw the rectangular texture you grabbed (with the stencil test on) >> into your destination buffer > > The stencil buffer is just what I needed. This example makes it very > easy to understand: > http://pseudogreen.org/bzr/pyglet_superbible/ch03/stencil.py > > My test code ended up looking like this (graphics lib more or less > wraps some basic pyglet/OpenGL calls): > pyglet.gl.glClearStencil(0) > pyglet.gl.glEnable(pyglet.gl.GL_STENCIL_TEST) > pyglet.gl.glClear(pyglet.gl.GL_STENCIL_BUFFER_BIT) > pyglet.gl.glStencilFunc(pyglet.gl.GL_NEVER, 0x0, 0x0) > pyglet.gl.glStencilOp(pyglet.gl.GL_INCR, pyglet.gl.GL_INCR, > pyglet.gl.GL_INCR) > > graphics.set_color(1,1,1,1) > graphics.draw_rect(self.x1,self.y1,self.x2,self.y2) > graphics.set_color(0,0,0,1) > graphics.draw_ellipse(self.x1,self.y1,self.x2,self.y2) > pyglet.gl.glStencilFunc(pyglet.gl.GL_NOTEQUAL, 0x1, 0x1) > pyglet.gl.glStencilOp(pyglet.gl.GL_KEEP, pyglet.gl.GL_KEEP, > pyglet.gl.GL_KEEP) > graphics.set_color(1,1,1,1) > graphics.draw_image(self.selection, self.x1, self.y1) > pyglet.gl.glDisable(pyglet.gl.GL_STENCIL_TEST) > That code draws an oval-shaped section of the image self.selection. > > On Nov 20, 3:16 pm, "Tristam MacDonald" <[EMAIL PROTECTED]> wrote: >> For a really simple approach, you can use multi-texturing with >> multiplicative blending against a mask texture. This will mask any areas >> where the mask texture is 0, and leave any areas where it is 1, but it may >> not be the most flexible approach. > I couldn't find any useful information about this method with a > rudimentary web search. > >> If you are using shaders, you can use a mask texture and a pixel shader to >> render only the unmasked portion of another texture (use the discard >> instruction for masked pixels). >> >> If you aren't using shaders, you may be able to work something out with the >> stencil buffer, although this wont be as straightforward. > My OpenGL knowledge is scattered and specialized, so I'm not using > shaders. The stencil buffer method was actually very straightforward: > use boilerplate setup code, draw mask, then more boilerplate, then > draw stuff, then more boilerplate. > >> C extensions are pretty much identical on OS X to linux, although you do >> need to pass the compiler a few different options. If you need help >> constructing a makefile for a C extension, I have several extension modules >> building cross-platform, so I can probably explain the process. > I tried looking for examples a few days ago but couldn't find anything > more recent than OS X 10.2, which had a much earlier version of > Python. Links to examples would be much appreciated. I'm decent with > C, but have used it primarily for homework assignments, so for now I'm > considering a C extension to be out of the scope of this project. > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "pyglet-users" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/pyglet-users?hl=en -~----------~----~----~----~------~----~------~--~---
