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[JuSil]

Hi,
I have an issue with gradient.

CMD_GRADIENT(400, 380, 0x336372, 400, 100, 0x84A3B2)

Looks nice in a Eve screen Editor, but in the display there are stripes about every 4millimeter. Gradient is a background, 800x480.
If I use gradient picture ARGP1555.raw, it looks ok.

I have Riverdi 7" eve3 BT815
//EVE 70
#define DWIDTH     800
#define DHEIGHT    480
#define PIXVOFFSET   0
#define PIXHOFFSET   0
#define HCYCLE     928
#define HOFFSET     88
#define HSYNC0       0
#define HSYNC1      48
#define VCYCLE     525
#define VOFFSET     32
#define VSYNC0       0
#define VSYNC1       3
#define PCLK         2
#define SWIZZLE      0
#define PCLK_POL     1
#define HSIZE      800
#define VSIZE      480
#define CSPREAD      0
#define DITHER       1

[BRT Community]

Hello,

The behaviour you are seeing can be attributed to how the CMD_Gradient command actually produces a gradient, this potentially mixed with poor viewing angels on the LCD can make the steps between colours more apparent.

We observed in some cases (depending on the LCD panel being used), the banding effect is related to LCD quality and configuration. In some cases, we found if we set:

REG_OUTBITS = 0x1B6 and REG_DITHER = 0x1

the banding effect is mitigated. These registers will set the RGB signals to 6 bits per channel and enable dithering.

Some other proposals would be to (1) Change the colour values from point a to b in the background gradient (2) Use a single line bitmap and repeat y to get the gradient effect. (3) use a full screen bitmap to produce the background image.

The following application uses a single line bitmap to create gradient background:
Example 8 – FT App MainMenu(+EVE2)

Best Regards,
BRT Community

[JuSil]

This REG_OUTBITS = 0x1B6 command fixed the problem, thanks.