Index for Section 3G

Alphabetical listing for G

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glRenderMode(3G)
NAME
  glRenderMode - set rasterization mode

SYNOPSIS
  GLint glRenderMode(
	  GLenum mode );

PARAMETERS
  mode
      Specifies the rasterization mode. Three values are accepted: GL_RENDER,
      GL_SELECT, and GL_FEEDBACK. The initial value is GL_RENDER.

DESCRIPTION
  glRenderMode() sets the rasterization mode. It takes one argument, mode,
  which can assume one of three predefined values:

  GL_RENDER
      Render mode. Primitives are rasterized, producing pixel fragments,
      which are written into the frame buffer. This is the normal mode and
      also the default mode.

  GL_SELECT
      Selection mode. No pixel fragments are produced, and no change to the
      frame buffer contents is made. Instead, a record of the names of
      primitives that would have been drawn if the render mode had been
      GL_RENDER is returned in a select buffer, which must be created (see
      glSelectBuffer()) before selection mode is entered.

  GL_FEEDBACK
      Feedback mode.  No pixel fragments are produced, and no change to the
      frame buffer contents is made. Instead, the coordinates and attributes
      of vertices that would have been drawn if the render mode had been
      GL_RENDER is returned in a feedback buffer, which must be created (see
      glFeedbackBuffer()) before feedback mode is entered.

  The return value of glRenderMode() is determined by the render mode at the
  time glRenderMode() is called, rather than by mode. The values returned for
  the three render modes are as follows:

  GL_RENDER
      0.

  GL_SELECT
      The number of hit records transferred to the select buffer.

  GL_FEEDBACK
      The number of values (not vertices) transferred to the feedback buffer.

  See the glSelectBuffer() and glFeedbackBuffer() reference pages for more
  details concerning selection and feedback operation.

NOTES
  If an error is generated, glRenderMode() returns 0 regardless of the
  current render mode.

ERRORS
  GL_INVALID_ENUM is generated if mode is not one of the three accepted
  values.

  GL_INVALID_OPERATION is generated if glSelectBuffer() is called while the
  render mode is GL_SELECT, or if glRenderMode() is called with argument
  GL_SELECT before glSelectBuffer() is called at least once.

  GL_INVALID_OPERATION is generated if glFeedbackBuffer() is called while the
  render mode is GL_FEEDBACK, or if glRenderMode() is called with argument
  GL_FEEDBACK before glFeedbackBuffer() is called at least once.

  GL_INVALID_OPERATION is generated if glRenderMode() is executed between the
  execution of glBegin() and the corresponding execution of glEnd().

ASSOCIATED GETS
  glGet() with argument GL_RENDER_MODE

SEE ALSO
  glFeedbackBuffer(3), glInitNames(3) ,glLoadName(3), glPassThrough(3),
  glPushName(3), glSelectBuffer(3)

Index for Section 3G

Alphabetical listing for G

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