HP b2600 Reference Manual page 151

in the feedback buffer. It can also occur after polygons with more than three edges are
broken up into triangles, if the GL implementation renders polygons by performing this
decomposition.
The glPassThrough command can be used to insert a marker into the feedback buffer.
See glPassThrough.
Following is the grammar for the blocks of values written into the feedback buffer. Each
primitive is indicated with a unique identifying value followed by some number of
vertices. Polygon entries include an integer value indicating how many vertices follow. A
vertex is fed back as some number of floating-point values, as determined by type. Colors
are fed back as four values in RGBA mode and one value in color index mode.
feedbackList
feedbackItem
point
lineSegment
vertex
polygon
polySpec
bitmap
pixelRectangle
vertex
passThru
vertex
2d
3d
3dColor
3dColorTexture
4dColorTexture
color
rgba
index
tex
value is a floating-point number, and n is a floating-point integer giving the number of
vertices in the polygon. GL_POINT_TOKEN, GL_LINE_TOKEN,
GL_LINE_RESET_TOKEN, GL_POLYGON_TOKEN, GL_BITMAP_TOKEN,
GL_DRAW_PIXEL_TOKEN, GL_COPY_PIXEL_TOKEN and
GL_PASS_THROUGH_TOKEN are symbolic floating-point constants.
GL_LINE_RESET_TOKEN is returned whenever the line stipple pattern is reset. The
data returned as a vertex depends on the feedback type.
Chapter 6
feedbackItem feedbackList | feedbackItem
point | lineSegment | polygon | bitmap | pixelRectangle | passThru
GL_POINT_TOKEN vertex
GL_LINE_TOKEN vertex vertex | GL_LINE_RESET_TOKEN vertex
GL_POLYGON_TOKEN n polySpec
polySpec vertex | vertex vertex vertex
GL_BITMAP_TOKEN vertex
GL_DRAW_PIXEL_TOKEN vertex |GL_COPY_PIXEL_TOKEN
GL_PASS_THROUGH_TOKEN value
2d | 3d | 3dColor | 3dColorTexture | 4dColorTexture
value value
value value value
value value value color
value value value color tex
value value value value color tex
rgba | index
value value value value
value
value value value value
F
glFeedbackBuffer
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