公开(公告)号：DE3750784D1

公开(公告)日：1995-01-12

申请号：DE3750784

申请日：1987-03-17

Applicant: IBM

Inventor： LIANG BOB CHAO-CHU ,  GONZALEZ-LOPEZ JORGE

IPC: G06F3/153 ,  G06F17/17 ,  G06T15/80 ,  G06F15/72 ,  G06F15/353

Abstract: Method and apparatus are disclosed for providing interpolated display characteristic values, such as intensity or Z value, for pels within a polygon to be displayed by a computer graphics display system. A scanning sequence generates pel addresses such that each pel address so generated is contiguous with a previously generated pel address. The parametric value rate of change in both the X and the Y direction is determined, and expressed as an integer value and a remainder quantity. The remainder quantity is used to determine a sequence, driven by pel address changes, by which the integer parametric value increment from pel to pel is incremented or decremented by one in a regular sequence that assures that the error in the computed parametric value for each pel never exceeds 0.5 parametric value units.

公开(公告)号：CA2059974A1

公开(公告)日：1992-11-09

申请号：CA2059974

申请日：1992-01-24

Applicant: IBM

Inventor： FERRACINI BRUNO ,  GONZALEZ-LOPEZ JORGE ,  PETTAZZI GIANCARLO

IPC: G06F3/153 ,  G06T3/40 ,  G09G5/36 ,  H04N1/393

Abstract: KI9-91-018 A METHOD AND APPARATUS FOR REDUCING A DIGITAL IMAGE Disclosed is a method and apparatus for reducing the size of a digital image from a first digital image to a second digital image by a specified scaling factor of G. The apparatus comprises an interpolator module configured to magnify the first digital image by a first scaling factor G1. The interpolator is further configured to output an intermediate digital image indicative of the magnified first image. The apparatus further comprises a shrinking module configured to shrink the intermediate digital image outputted by the interpolator module by a second scaling factor G2 to thereby generate the second digital image. Scaling factor G2 is a power of two.

公开(公告)号：CA1309200C

公开(公告)日：1992-10-20

申请号：CA573782

申请日：1988-08-04

Applicant: IBM

Inventor： GONZALEZ-LOPEZ JORGE ,  LIANG BOB C C

IPC: G06T15/40 ,  G09B9/30 ,  G06F15/72

Abstract: HIDDEN LINE REMOVAL METHOD WITH MODIFIED DEPTH BUFFER Polygon vertex data is processed in three steps to create a graphics display without hidden lines and without gaps in the displayed lines. The technique permits the processing of triangles rather than polygons having four or more sides. In the first step, the Z values for the display points for the visible edges of the polygons are identified and assigned a reserved value ZCLOSE in a frame buffer. In the second step, the polygons are tessellated into triangles and the Z values for the display points on the triangles are computed and each depth buffer storage location is updated so as to contain the value of points closest to the viewpoint while the frame buffer is written with a background color. In the final step, the Z values for the display points of the polygon edges are again computed and compared-with the corresponding Z values in the depth buffer. The depth buffer is updated with the computed values if the stored value is equal to ZCLOSE or if the computed value represents a position closer to the viewpoint than the stored value and the frame buffer is then written with a foreground color for the display point in question.

公开(公告)号：DE69031204T2

公开(公告)日：1998-02-12

申请号：DE69031204

申请日：1990-10-17

Applicant: IBM

Inventor： GONZALEZ-LOPEZ JORGE ,  LANZONI THOMAS PAUL

IPC: G06T15/80 ,  G06T11/20

Abstract: In a computer graphics display system, a method and processor are disclosed for drawing a 'polygon with edge'-type primitive encountered in certain high level graphics interface programs. Both the method and processor use a mask buffer organized into a plurality of addressable M x N constituent pixels, each pixel preferably being two bits deep. The method includes: masking the pixels in the mask buffer corresponding to the boundary to the polygon; drawing the pixels in the frame buffer of the display system corresponding to the boundary of the polygon; and drawing the pixels in the frame buffer corresponding to the interior of the polygon with reference to the content of the mask buffer. Corresponding processing steps for writing Z values in a depth buffer are also described. In addition, specific algorithms for implementing the method are set forth, along with an embodiment of a display processor implementing the method.

公开(公告)号：DE3853336T2

公开(公告)日：1995-09-28

申请号：DE3853336

申请日：1988-10-13

Applicant: IBM

Inventor： GONZALEZ-LOPEZ JORGE ,  HEMPEL BRUCE CARLTON ,  LIANG BOB CHAO-CHU

IPC: G06F17/50 ,  G06T15/50 ,  G06T11/00

Abstract: A lighting model processing system for a computer graphics workstation's shading function includes multiple floating point processing stages arranged and operated in pipeline. Each stage is constructed from one or more identical floating point processors. The lighting model processing system supports one or more light sources illuminating an object to be displayed, with parallel or perspective projection. Dynamic partitioning can be used to balance the computational workload among various of the processors in order to avoid a bottleneck in the pipeline. The high throughput of the pipeline system makes possible the rapid calculation and display of high quality shaded images.

公开(公告)号：DE3750784T2

公开(公告)日：1995-07-13

申请号：DE3750784

申请日：1987-03-17

Applicant: IBM

Inventor： LIANG BOB CHAO-CHU ,  GONZALEZ-LOPEZ JORGE

IPC: G06F3/153 ,  G06F17/17 ,  G06T15/80 ,  G06T11/20

Abstract: Method and apparatus are disclosed for providing interpolated display characteristic values, such as intensity or Z value, for pels within a polygon to be displayed by a computer graphics display system. A scanning sequence generates pel addresses such that each pel address so generated is contiguous with a previously generated pel address. The parametric value rate of change in both the X and the Y direction is determined, and expressed as an integer value and a remainder quantity. The remainder quantity is used to determine a sequence, driven by pel address changes, by which the integer parametric value increment from pel to pel is incremented or decremented by one in a regular sequence that assures that the error in the computed parametric value for each pel never exceeds 0.5 parametric value units.

公开(公告)号：DE3853336D1

公开(公告)日：1995-04-20

申请号：DE3853336

申请日：1988-10-13

Applicant: IBM

Inventor： GONZALEZ-LOPEZ JORGE ,  HEMPEL BRUCE CARLTON ,  LIANG BOB CHAO-CHU

IPC: G06F17/50 ,  G06T15/50 ,  G06T11/00

Abstract: A lighting model processing system for a computer graphics workstation's shading function includes multiple floating point processing stages arranged and operated in pipeline. Each stage is constructed from one or more identical floating point processors. The lighting model processing system supports one or more light sources illuminating an object to be displayed, with parallel or perspective projection. Dynamic partitioning can be used to balance the computational workload among various of the processors in order to avoid a bottleneck in the pipeline. The high throughput of the pipeline system makes possible the rapid calculation and display of high quality shaded images.

公开(公告)号：DE3750211T2

公开(公告)日：1995-02-02

申请号：DE3750211

申请日：1987-08-31

Applicant: IBM

Inventor： GONZALEZ-LOPEZ JORGE

IPC: G09G5/397 ,  G09G5/00 ,  G09G5/06 ,  G09G5/36 ,  G09G5/395 ,  G09G5/399 ,  G09G5/42 ,  G09G1/16 ,  G09G1/28

Abstract: A graphics workstation includes a microprocessor (10), a system memory (40) for storing graphics and image (for example, optical scanner) data. A graphics data processor (20) and an image data processor (80) are connected to receive respective data from the memory and operate to modify the data and apply it to a pair of frame buffers (30, 32) which are interleaved such that while one is applying data to a display device, the other is receiving data from one or both of the graphics and image data processors.