Posted on March 21, 2018 at 20:20 Hi, I've been working on a UI for past couple weeks,
I've successfully created functionality for drawing bitmaps (with or without alpha), anti-aliased fonts and solid rectangles / lines using Chrom-ART / DMA2D
I am however currently unsure how to do rectangle fills with transparency. I assumed that DMA2D_R2M would accept a ARGB color and layer configurations, however that was not the case.
Can someone explain in rough lines how I can fill a rectangle, that contains an alpha channel, over an existing drawn area?
Thanks
http://preview.ibb.co/htzuzc/IMG_20180321_202jpg
My current bitmap/font character drawing function:
void
LCD
::
DMA_DrawBitmap
(
void
*pSrc
,
void
*pDst
,
uint32_t
xSize
,
uint32_t
ySize
,
uint32_t
ColorMode
,
uint32_t
inputAlpha
,
uint32_t
inputOffset) {
hDma2dHandler
.
Init
.
Mode
=
DMA2D_M2M_BLEND
;
hDma2dHandler
.
Init
.
ColorMode
=
hLtdcHandler
.
LayerCfg
[
0
].
PixelFormat
;
hDma2dHandler
.
Init
.
OutputOffset
=
SCREEN_WIDTH
- xSize
;
hDma2dHandler
.
LayerCfg
[
0
].
AlphaMode
=
DMA2D_NO_MODIF_ALPHA
;
hDma2dHandler
.
LayerCfg
[
0
].
InputColorMode
=
hLtdcHandler
.
LayerCfg
[
0
].
PixelFormat
;
hDma2dHandler
.
LayerCfg
[
0
].
InputAlpha
=
0
;
hDma2dHandler
.
LayerCfg
[
0
].
InputOffset
=
SCREEN_WIDTH
- xSize
;
/* Foreground Configuration */
hDma2dHandler
.
LayerCfg
[
1
].
AlphaMode
=
DMA2D_NO_MODIF_ALPHA
;
hDma2dHandler
.
LayerCfg
[
1
].
InputAlpha
= inputAlpha
;
hDma2dHandler
.
LayerCfg
[
1
].
InputColorMode
= ColorMode
;
hDma2dHandler
.
LayerCfg
[
1
].
InputOffset
= inputOffset
;
hDma2dHandler
.
Instance
=
DMA2D
;
/* DMA2D Initialization */
if
(HAL_DMA2D_Init(&
hDma2dHandler
) ==
HAL_OK
) {
if
(HAL_DMA2D_ConfigLayer(&
hDma2dHandler
,
0
) ==
HAL_OK
&& HAL_DMA2D_ConfigLayer(&
hDma2dHandler
,
1
) ==
HAL_OK
) {
if
(HAL_DMA2D_BlendingStart(&
hDma2dHandler
,
(
uint32_t
) pSrc
,
(
uint32_t
) pDst
,
(
uint32_t
) pDst
,
xSize
,
ySize) ==
HAL_OK
) {
HAL_DMA2D_PollForTransfer(&
hDma2dHandler
,
500
)
;
}
}
}
}
And rectangle fill function:
void
LCD
::
DMA_FillRect
(
void
*pSrc
,
void
*pDst
,
uint32_t
xSize
,
uint32_t
ySize
,
uint32_t
ColorMode) {
/* Configure the DMA2D Mode, Color Mode and output offset */
hDma2dHandler
.
Init
.
Mode
=
DMA2D_M2M_PFC
;
hDma2dHandler
.
Init
.
ColorMode
=
hLtdcHandler
.
LayerCfg
[
0
].
PixelFormat
;
hDma2dHandler
.
Init
.
OutputOffset
=
SCREEN_WIDTH
- xSize
;
/* Foreground Configuration */
hDma2dHandler
.
LayerCfg
[
1
].
AlphaMode
=
DMA2D_NO_MODIF_ALPHA
;
hDma2dHandler
.
LayerCfg
[
1
].
InputAlpha
=
0xFF
;
hDma2dHandler
.
LayerCfg
[
1
].
InputColorMode
= ColorMode
;
hDma2dHandler
.
LayerCfg
[
1
].
InputOffset
=
0
;
hDma2dHandler
.
Instance
=
DMA2D
;
/* DMA2D Initialization */
if
(HAL_DMA2D_Init(&
hDma2dHandler
) ==
HAL_OK
) {
if
(HAL_DMA2D_ConfigLayer(&
hDma2dHandler
,
1
) ==
HAL_OK
) {
if
(HAL_DMA2D_Start(&
hDma2dHandler
,
(
uint32_t
) pSrc
,
(
uint32_t
) pDst
,
xSize
,
ySize) ==
HAL_OK
) {
HAL_DMA2D_PollForTransfer(&
hDma2dHandler
,
500
)
;
}
}
}
}
graphics lcd ui chrom-art dma2d
