SH7205 Datasheet, PDF (1457/1904 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7200 Series

Section 26 2D Graphics Engine (2DG)
(f) Summary of Color Gradation Processing
Since the color gradation processing function is installed only on the input B path, it cannot be
performed on the input A path. Irrespective of blending, color gradation processing is available
only during blit operations. During such operations, chromakey processing or logical operations
cannot be executed at the same time. Although resizing is possible, the use of it is not
recommended in situations where character quality is important. Where possible, resizing should
be avoided. The color gradation processing is not designed to accommodate partial resizing.
The basic operations of the color gradation processing are as follows:
1. DMA-transfers only a specified area from any font area, created with α (4 bits) on the
SDRAM, to the 2DG.
2. Expands the color that is set in the GR_BRDCOL register.
3. Creates a color gradation according to the α value by weighting (multiplying) with the
transferred α value and a specified color.
Depending on how a font is created using an α value, pseudo-anti-alias effects can also be
produced.
• Color gradation processing example (1)
Blit mode setting: Blit mode (GR_BLTMODE register, BTYPE bits = 00)
Blending operation: Without blending (GR_BLTPLY register, SB_STEN bit = 1 and SA_STEN
bit = 0)
Rev. 1.00 Mar. 25, 2008 Page 1425 of 1868
REJ09B0372-0100