11-6
Display Interface
Power 9100 User Interface Controller
11.2.1 Parameter engine
The parameter engine prepares drawing operations for the drawing engine;
its function is to take input coordinates from the host and convert them to a
form usable by the drawing engine. The input parameters include the x,y
vertices of polygons and the corners of bit block-transfer (BitBlt) regions.
The parameter engine tests the vertices against window and screen
boundaries, tests for exceptions, and performs trivial rejection. It transfers
commands that pass these tests to the drawing engine for execution.
The parameter engine prepares four kinds of polygons for drawing. These
are quadrilaterals, triangles, lines, and points. It converts points, lines, and
triangles into quadrilaterals by automatically replicating vertices. For
example, a point is a quadrilateral with all four vertices at the same x,y
location. Only a single vertex is required to draw a point; the parameter
engine passes four copies of that vertex to the drawing engine and instructs
it to draw a quad.
The parameter engine also handles screen-to-screen BitBlt and two kinds
of host-to-screen BitBlt operations; one is optimized for text and the other
is optimized for graphics. The parameter engine handles all exception
testing and host accesses to parameter engine registers and passes
operations that write to the display to the drawing engine.
11.2.2 Drawing engine
The drawing engine performs three functions. These are quadrilateral
drawing (quad operations), screen-to-screen BitBlt (blit operations), and
host-to-screen (pixel operations).
The quad operation draws quadrilaterals in one of two modes: X11 mode,
an X-Windows compatible mode; and oversized mode. Triangles, lines,
and points can always be rendered correctly, but the drawing engine cannot
draw horizontally convex quadrilaterals. That is, it cannot cross from the
inside to the outside of the same object more than once per scan line.
The blit operation copies a rectangular area on the display from one screen
location to another.
The pixel8 operation takes 8-bits-per-pixel color data (up to four pixels per
word), and writes them to the frame buffer.
11.2.3 Frame buffer controller
The Power 9100 controls the frame buffer directly. Frame buffer control
registers in the P9100 determine the VRAM refresh rate, the screen size,
and single or double-buffering; they also select interleaved or
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Содержание SPARCbook 3 series
Страница 1: ...Series Technical Reference Manual 980327 02 3 S3GX_TRMBook Page i Friday September 19 1997 11 39 am...
Страница 8: ...viii S3GX_TRMBook Page viii Friday September 19 1997 11 39 am...
Страница 28: ...1 16 Architecture Overview Microcontroller Subsystem S3GX_TRMBook Page 16 Friday September 19 1997 11 39 am...
Страница 44: ...2 16 The SPARC CPU SBus Controller S3GX_TRMBook Page 16 Friday September 19 1997 11 39 am...
Страница 76: ...5 8 SCSI Controller DMA Support S3GX_TRMBook Page 8 Friday September 19 1997 11 39 am...
Страница 82: ...6 6 Ethernet Interface DMA Support for Network Operations S3GX_TRMBook Page 6 Friday September 19 1997 11 39 am...
Страница 96: ...7 14 PCMCIA Interface Microcontroller Registers S3GX_TRMBook Page 14 Friday September 19 1997 11 39 am...
Страница 146: ...9 28 MODEM Class 2 Fax Command Set S3GX_TRMBook Page 28 Friday September 19 1997 11 39 am...
Страница 180: ...11 30 Display Interface RAMDAC S3GX_TRMBook Page 30 Friday September 19 1997 11 39 am...
Страница 210: ...B 10 Connector Information Removable Hard Drive SCSI Connector S3GX_TRMBook Page 10 Friday September 19 1997 11 39 am...
Страница 216: ...Index vi S3GX_TRMBook Page vi Friday September 19 1997 11 39 am...