Samsung S5PC100, Руководство пользователя

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2D-ACCELERATOR S5PC100 USER’S MANUAL (REV1.0)
5.1 PRIMITIVE DRAWING
Primitive Drawing determines the pixels to fill, and pass their coordinates to the next stage for further operations.
2D-ACCELERATOR supports three types of primitive drawing: 1) Line/ Point drawing; 2) Bit block transfer; 3)
Color expansion.
5.1.1 Line/Point Drawing
Line Drawing renders a line between the starting point (sx, sy) and the ending point (ex, ey) specified by the user.
If the distance of these two points along y axis is greater than that along x axis ( |ey - sy| > |ex - sx| ), the Major
Axis should be set to y-axis; otherwise, x-axis. If y-axis is the Major Axis, the y-coordinate of a pixel on the line is
increased or decreased by 1 from its preceding pixel, while the x-coordinate increased or decreased by X-INCR
(smaller than 1). In the same vein, if x-axis is the Major Axis, the x-coordinate is increased or decreased by 1
while the y-coordinate by Y-INCR. Note that X-INCR and Y-INCR should be given in 2’s complement format as
shown below. . For example, 1.75 can be represented by 00000000001.11000000000, while -1.75 by
1111111110.01000000000.
Related Registers
COORD_0 Coordinate of the starting point
COORD_2 Coordinate of the ending point (Ignored if a point is rendered).
X-INCR
X increment value (Ignored if x-axis is the Major Axis or a point is rendered).
X-INCR = (ex-sx)/ |ey - sy|
Y-INCR
Y increment value (Ignored if y-axis is the Major Axis or a point is rendered).
Y-INCR = (ey – sy)/ |ex - sx|
FG_COLOR The color of the drawn line/ point
CMD0_REG
Configure the line/ point drawing parameters, such as whether the Major-Axis is x-
axis or y-axis, whether to draw a line or a point, and etc. Note that writing to this
register starts the rendering process.
5.1.2 Bit Block Transfer
A Bit Block Transfer is a transformation of a rectangular block of pixels. Typical applications include copying the
off-screen pixel data to frame buffer, combining to bitmap patterns by Raster Operation, changing the dimension
of a rectangular image etc.
On-Screen Rendering
On-screen bit block transfer copies a rectangular block of pixels on screen to another position on the same
screen. On-screen rendering has the following restriction:
1) SRC_BASE_ADDR = DEST_BASE_ADDR
2) SRC_HORI_RES_REG = DEST_HORI_RES_REG
3) SRC_COLOR_MODE = DEST_COLOR_MODE
4) If the destination block overlaps with the source block, stretch mode and rotation must not be used.
9.5-4