Module: Rubygame::GL

Defined in:
ext/rubygame/rubygame_gl.c,
ext/rubygame/rubygame_gl.c

Overview

The GL module provides an interface to SDL’s OpenGL-related functions, allowing a Rubygame application to create hardware-accelerated 3D graphics with OpenGL.

Please note that Rubygame itself does not provide an interface to OpenGL functions – only functions which allow Rubygame to work together with OpenGL. You will need to use another library, for example ruby-opengl, to actually create graphics with OpenGL.

Users who wish to use Rubygame Surfaces as textures in OpenGL should see also the Surface#pixels method.

Constant Summary collapse

RED_SIZE = 
INT2NUM(SDL_GL_RED_SIZE)
GREEN_SIZE = 
INT2NUM(SDL_GL_GREEN_SIZE)
BLUE_SIZE = 
INT2NUM(SDL_GL_BLUE_SIZE)
ALPHA_SIZE = 
INT2NUM(SDL_GL_ALPHA_SIZE)
BUFFER_SIZE = 
INT2NUM(SDL_GL_BUFFER_SIZE)
DOUBLEBUFFER = 
INT2NUM(SDL_GL_DOUBLEBUFFER)
DEPTH_SIZE = 
INT2NUM(SDL_GL_DEPTH_SIZE)
STENCIL_SIZE = 
INT2NUM(SDL_GL_STENCIL_SIZE)
ACCUM_RED_SIZE = 
INT2NUM(SDL_GL_ACCUM_RED_SIZE)
ACCUM_GREEN_SIZE = 
INT2NUM(SDL_GL_ACCUM_GREEN_SIZE)
ACCUM_BLUE_SIZE = 
INT2NUM(SDL_GL_ACCUM_BLUE_SIZE)
ACCUM_ALPHA_SIZE = 
INT2NUM(SDL_GL_ACCUM_ALPHA_SIZE)

Class Method Summary collapse

Class Method Details

.get_attrib(attrib) ⇒ Integer

Return the value of the the SDL/OpenGL attribute identified by attrib, which should be one of the constants defined in the Rubygame::GL module. See #set_attrib for a list of attribute constants.

This method is useful after using #set_attrib and calling Screen#set_mode, to make sure the attribute is the expected value.

Returns:

  • (Integer) 


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# File 'ext/rubygame/rubygame_gl.c', line 53

VALUE rbgm_gl_getattrib(VALUE module, VALUE attr)
{
  int val;
  if(SDL_GL_GetAttribute(NUM2INT(attr),&val)==-1)
    rb_raise(eSDLError,"GL get attribute failed: %s",SDL_GetError());
  return INT2NUM(val);
}

.set_attrib(attrib, value) ⇒ nil

Set the SDL/OpenGL attribute attrib to value. This should be called before you call Screen#set_mode with the OPENGL flag. You may wish to use #get_attrib after calling Screen#set_mode to confirm that the attribute is set to the desired value.

The full list of SDL/OpenGL attribute identifier constants (located under the Rubygame::GL module) is as follows:

RED_SIZE

Size of framebuffer red component, in bits.

GREEN_SIZE

Size of framebuffer green component, in bits.

BLUE_SIZE

Size of framebuffer blue component, in bits.

ALPHA_SIZE

Size of framebuffer alpha (opacity) component, in bits.

BUFFER_SIZE

Size of framebuffer, in bits.

DOUBLEBUFFER

Enable or disable double-buffering.

DEPTH_SIZE

Size of depth buffer, in bits.

STENCIL_SIZE

Size of stencil buffer, in bits.

ACCUM_RED_SIZE

Size of accumulation buffer red component, in bits.

ACCUM_GREEN_SIZE

Size of accumulation buffer green component, in bits.

ACCUM_BLUE_SIZE

Size of accumulation buffer blue component, in bits.

ACCUM_ALPHA_SIZE

Size of accumulation buffer alpha component, in bits.

Returns:

  • (nil) 


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# File 'ext/rubygame/rubygame_gl.c', line 86

VALUE rbgm_gl_setattrib(VALUE module,VALUE attr,VALUE val)
{
  if(SDL_GL_SetAttribute(NUM2INT(attr),NUM2INT(val))==-1)
    rb_raise(eSDLError,"GL set attribute failed: %s",SDL_GetError());
  return Qnil;
}

.swap_buffers ⇒ nil

Swap the back and front buffers, for double-buffered OpenGL displays. Should be safe to use (albeit with no effect) on single-buffered OpenGL displays.

Returns:

  • (nil) 


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# File 'ext/rubygame/rubygame_gl.c', line 100

VALUE rbgm_gl_swapbuffers(VALUE module)
{
  SDL_GL_SwapBuffers();
  return Qnil;
}