> Le Samedi 30 Juillet 2011 00:19:41, Kevin Fishburne a écrit : > > I've been researching this for hours and nothing I try works. The image > > used for the texture has an alpha channel, but it is displayed as black > > instead of transparent. I'm starting to think that the line: > > > > Gl.TexImage2D(t1) > > > > isn't passing the presence of an alpha channel to OpenGL, but that's > > just a guess. Normally you specify the image format there, but those > > parameters aren't supported yet in the gb3 implementation. > > > > The project is attached. You can move the little wizard around with the > > ASDW keys and rotate with the QE keys. Any help appreciated...I'm going > > crazy and am calling it quits for the night > > This is what i do in the sdl component to get alpha blending: > > glEnable(GL_BLEND); > glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); > > So it should be in gambas3 code: > > Gl.Enable(Gl.GL_BLEND) > Gl.BlendFunc(Gl.GL_SRC_ALPHA, Gl.GL_ONE_MINUS_SRC_ALPHA) > > ++ >
If, in GltextureMapping.c:238: glTexImage2D(GL_TEXTURE_2D, VARGOPT(Level, 0), 3, image->width, image->height, VARGOPT(Border, 0), format, GL_UNSIGNED_BYTE, image->data); I replace the "3" by "4", as it is in line 225, I get the transparency. According to the documentation, this number is the number of color components in the texture, which should be 4 for RGBA. I suggest that this number should be 3 if the image format is RGB or BGR, and 4 if the image format is RGBA, RGBX, BGRA, tec. Another point. I opened the file GLUtextureImage.c (searching for GL.TexImage2D), and I noticed that GLUBUILD1DMIPMAPS use IMAGE_get to read its image argument (which does error checking), but not GLUBUILD2DMIPMAPS, which should lead to possible segfaults... Laurent, I let you modify the code (if I'm not wrong) :-) -- Benoît Minisini ------------------------------------------------------------------------------ Got Input? Slashdot Needs You. Take our quick survey online. Come on, we don't ask for help often. Plus, you'll get a chance to win $100 to spend on ThinkGeek. http://p.sf.net/sfu/slashdot-survey _______________________________________________ Gambas-user mailing list Gambas-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gambas-user