Cinder Hints

I’ve been digging into Cinder quite a bit in the past few weeks. Getting comfortable with a framework comes with many moments of enlightenment. Consider this a growing list documenting such moments.

• Don’t forget to add a carriage return to the end of your Resources.h file. Without a hard return at the end of the file, that is, after the last resource definition, your code will not compile. Attempting to compile with Visual C++ you will see an error that looks something like this: fatal error RC1004: unexpected end of file found
• When rendering text using TextLayout, use setColor() before addLine().
• Surface::Iter does not iterate pixels in a predictable manner. Use the getPos() method on the iterator object to return a Vec2i and use it’s x and y properties to determine which pixel is currently being examined. Check out a recent article for more information on this.
• Blending: Specifying a blend mode for a texture can be a bit tricky. Here are some combinations I’ve found that work well.
  • Screen: glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_COLOR);
  • Additive: glBlendFunc(GL_ONE, GL_ONE);
  • Multiply ( non-transparent image only ): glBlendFunc(GL_ZERO, GL_SRC_COLOR);

  Example Usage:

  •                gl::enableAlphaBlending();
                   glBlendFunc(GL_ZERO, GL_SRC_COLOR);
                   gl::draw( texture );
                   gl::disableAlphaBlending();

• When adding points to a Shape2d or Path2d you must set the first point using moveTo(). Your app will crash otherwise.
• You must set glLineWidth() before calling glBegin( GL_LINES )
  Example Usage:

                 glLineWidth( 10.0f );
                 glBegin( GL_LINES );