Samsung S5PC100, User Manual

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S5PC100 USER’S MANUAL (REV1.0) 3D-ACCELERATOR
9.6-55
6.3.2 Depth Offset Registers (FGRA)
The offset value o for a polygon is
o = m * r * units .
m means the maximum value of incremental ratio to polygon’s depth value. o can have the value of [0, 1] range.
And, r (0x34000001) is a H/W characteristic value related to the usable resolution of the depth buffer. The factor
scales m and the units scales r . The offset value o is applied to depth values of all pixels of a polygon.
y
RA_DOffEn, R/W, Address = 0x0003_8004
y
RA_DOffFactor, R/W, Address = 0x0003_8008
y
RA_DOffUnits, R/W, Address = 0x0003_800C
y
RA_DOffRIn, R/W, Address = 0x0003_8010
RA_DOffEn Bit Description Reset Value
Reserved [31:1] Reserved 0
DOffEn [0] Depth offset usage control register
0b = Disable 1b = Enable 0b
RA_DOffFactor Bit Description Reset Value
DOffFactor [31:0] Factor scales the max depth slope of the polygon.
Used to calculate the depth offset value. 0x0
RA_DOffUnits Bit Description Reset Value
DOffUnits [31:0] Unit scale an implementation dependent constant that relates
to the usable resolution of the depth buffer.
Used to calculate the depth offset value. 0x0
RA_DOffRIn Bit Description Reset Value
DOffRIn [31:0] An implementation dependent constant that relates to the
usable resolution of the depth buffer.
Used to calculate the depth offset value of a polygon. 0x34000001