公开(公告)号：ZA9108049B

公开(公告)日：1992-07-29

申请号：ZA9108049

申请日：1991-10-08

Applicant: IBM

Inventor： BRASE DEBORAH DIANE ,  DEBORAH DIANE BRASE ,  LARKY STEVEN PHILIP ,  STEVEN PHILIP LARKY ,  CLAIR JOE CHRISTOPHER ST ,  JOE CHRISTOPHER ST CLAIR ,  SIDOLI PAOLO ,  PAOLO SIDOLI

IPC: G06F3/153 ,  G06F3/033 ,  G06F3/048 ,  G06T1/60 ,  G06T11/80 ,  G06T15/30 ,  G09G5/36 ,  G09G

CPC classification number: G06F3/04842 ,  G06T15/30

公开(公告)号：ZA918049B

公开(公告)日：1992-07-29

申请号：ZA918049

申请日：1991-10-08

Applicant: IBM

Inventor： BRASE DEBORAH DIANE ,  DEBORAH DIANE BRASE ,  LARKY STEVEN PHILIP ,  STEVEN PHILIP LARKY ,  CLAIR JOE CHRISTOPHER ST ,  JOE CHRISTOPHER ST CLAIR ,  SIDOLI PAOLO ,  PAOLO SIDOLI

IPC: G06F3/153 ,  G06F3/033 ,  G06F3/048 ,  G06T1/60 ,  G06T11/80 ,  G06T15/30 ,  G09G5/36 ,  G09G

Abstract: In a system and process for picking three dimensional objects from images depicted on a video display the displayed objects are selectively rerendered. During such rerendering the object pixels are compared in depth to the data in a Z buffer 9 for determining visibility. The number and size of the objects subject to rerendering by the rasterization processor 2 is constrained by using the front end graphics processor 1 to define object extents and by rerendering only extents which have been clipped to the boundaries of the pick window. The rerendering operation does not alter the three dimensional graphics image stored in and repetitively scanned from the frame buffer 3. Selection between multiple objects within the pick window can include a weighted comparison using a pick plane memory 20 to store visibility data by object.