01、Vertex processing in the OpenGL pipeline
02、The actions of the overall graphics pipeline
03
the modeling and viewing transformations are combined into
the ModelView transformation, and new modeling transformations are multi-
plied into this as they are defined.
A transformation stack is maintained for the
ModelView and Projection transformations, with the current version at the top
of the stack. The glPushMatrix( ) and glPopMatrix( ) operations let you save
and restore modeling environments.
The ModelViewProjection transformation is
the product of the ModelView and Projection transformations, and is updated
whenever the ModelView transformation or Projection Transformation is
updated. The ModelViewProjection transformation is applied to individual
vertices to place them into clip space.
The system also maintains another trans-
formation, the Normal transformation, calculated as the inverse of the transpose
of the ModelView transformation, which handles the problem of ensuring that
the normal can be correctly used for lighting and other operations
A simplified view of the OpenGL render-ing pipeline.
