VT8601 Via, VT8601 Datasheet - Page 130

• Manufacturer Part Number: VT8601
• Description: Slot-1 / Socket-370 PCI North Bridge
• Manufacturer: Via

Texture Coordinate Parameters
Texture parameters are used for texture mapping.
consist of starting values, incremental along the X and Y axis.
DoubleWord 0 – Initial U Value
DoubleWord 1 – Initial U Value
DoubleWord 2 – X-Axis U Gradient
DoubleWord 3 – Y-Axis U Gradient
DoubleWord 4 – X-Axis V Gradient
DoubleWord 5 – Y-Axis V Gradient
Revision 1.3 September 8, 1999
31-0 Initial U Value
31-0 Initial U Value
31-0 X-Axis U Gradient
31-0 Y-Axis U Gradient
31-0 X-Axis V Gradient
31-0 Y-Axis V Gradient
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Initial U value on main edge (left edge of trapezoid or
long edge of triangle). Signed 16.16 integer.
Initial U value on main edge (left edge of trapezoid or
long edge of triangle). Signed 16.16 integer.
Gradient of U along the X axis over the primitive
surface. Signed 16.16 number.
Gradient of U along the Y axis over the primitive
surface. Signed 16.16 number.
Gradient of V along the X axis over the primitive
surface. Signed 16.16 number.
Gradient of V along the Y axis over the primitive
surface. Signed 16.16 number.
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Perspective Factor Parameters
Perspective factor parameters are used for perspective
corrected texture mapping. They consist of W starting values
incremental along the X and Y axis.
DoubleWord 0 – Initial W Value
DoubleWord 1 – X-Axis W Gradient
DoubleWord 2 – Y-Axis W Gradient
31-0 Initial W Value
31-0 X-Axis W Gradient
31-0 Y-Axis W Gradient
Initial W value on main edge (left edge of trapezoid
or long edge of triangle). Signed 4.28 integer.
Gradient of W along the X axis over the primitive
surface. Signed 4.28 number.
Gradient of W along the Y axis over the primitive
surface. Signed 4.28 number.
VT8601 Apollo ProMedia
3D Graphics Engine Registers