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chore(style): remove the trailing space from all source files (#3188)

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Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
This commit is contained in:
Xiang Xiao
2022-03-21 18:25:51 +08:00
committed by GitHub
parent 46bd054ad4
commit 4c4f954059
223 changed files with 1719 additions and 1719 deletions
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28
docs/widgets/core/canvas.md
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@@ -1,5 +1,5 @@
```eval_rst
.. include:: /header.rst
.. include:: /header.rst
:github_url: |github_link_base|/widgets/core/canvas.md
```
# Canvas (lv_canvas)
@@ -7,8 +7,8 @@
## Overview
A Canvas inherits from [Image](/widgets/core/img) where the user can draw anything.
Rectangles, texts, images, lines, arcs can be drawn here using lvgl's drawing engine.
A Canvas inherits from [Image](/widgets/core/img) where the user can draw anything.
Rectangles, texts, images, lines, arcs can be drawn here using lvgl's drawing engine.
Additionally "effects" can be applied, such as rotation, zoom and blur.
@@ -19,31 +19,31 @@ Additionally "effects" can be applied, such as rotation, zoom and blur.
### Buffer
The Canvas needs a buffer in which stores the drawn image.
To assign a buffer to a Canvas, use `lv_canvas_set_buffer(canvas, buffer, width, height, LV_IMG_CF_...)`.
To assign a buffer to a Canvas, use `lv_canvas_set_buffer(canvas, buffer, width, height, LV_IMG_CF_...)`.
Where `buffer` is a static buffer (not just a local variable) to hold the image of the canvas.
For example,
`static lv_color_t buffer[LV_CANVAS_BUF_SIZE_TRUE_COLOR(width, height)]`.
`static lv_color_t buffer[LV_CANVAS_BUF_SIZE_TRUE_COLOR(width, height)]`.
`LV_CANVAS_BUF_SIZE_...` macros help to determine the size of the buffer with different color formats.
The canvas supports all the built-in color formats like `LV_IMG_CF_TRUE_COLOR` or `LV_IMG_CF_INDEXED_2BIT`.
The canvas supports all the built-in color formats like `LV_IMG_CF_TRUE_COLOR` or `LV_IMG_CF_INDEXED_2BIT`.
See the full list in the [Color formats](/overview/image.html#color-formats) section.
### Indexed colors
For `LV_IMG_CF_INDEXED_1/2/4/8` color formats a palette needs to be
For `LV_IMG_CF_INDEXED_1/2/4/8` color formats a palette needs to be
initialized with `lv_canvas_set_palette(canvas, 3, LV_COLOR_RED)`. It sets pixels with *index=3* to red.
### Drawing
To set a pixel's color on the canvas, use `lv_canvas_set_px_color(canvas, x, y, LV_COLOR_RED)`.
With `LV_IMG_CF_INDEXED_...` the index of the color needs to be passed as color.
With `LV_IMG_CF_INDEXED_...` the index of the color needs to be passed as color.
E.g. `lv_color_t c; c.full = 3;`
To set a pixel's opacity with `LV_IMG_CF_TRUE_COLOR_ALPHA` or `LV_IMG_CF_ALPHA_...` format on the canvas, use `lv_canvas_set_px_opa(canvas, x, y, opa)`.
`lv_canvas_fill_bg(canvas, LV_COLOR_BLUE, LV_OPA_50)` fills the whole canvas to blue with 50% opacity. Note that if the current color format doesn't support colors (e.g. `LV_IMG_CF_ALPHA_2BIT`) the color will be ignored.
`lv_canvas_fill_bg(canvas, LV_COLOR_BLUE, LV_OPA_50)` fills the whole canvas to blue with 50% opacity. Note that if the current color format doesn't support colors (e.g. `LV_IMG_CF_ALPHA_2BIT`) the color will be ignored.
Similarly, if opacity is not supported (e.g. `LV_IMG_CF_TRUE_COLOR`) it will be ignored.
An array of pixels can be copied to the canvas with `lv_canvas_copy_buf(canvas, buffer_to_copy, x, y, width, height)`.
An array of pixels can be copied to the canvas with `lv_canvas_copy_buf(canvas, buffer_to_copy, x, y, width, height)`.
The color format of the buffer and the canvas need to match.
To draw something to the canvas use
@@ -59,7 +59,7 @@ To draw something to the canvas use
The draw function can draw to any color format. For example, it's possible to draw a text to an `LV_IMG_VF_ALPHA_8BIT` canvas and use the result image as a [draw mask](/overview/drawing) later.
### Transformations
`lv_canvas_transform()` can be used to rotate and/or scale the image of an image and store the result on the canvas.
`lv_canvas_transform()` can be used to rotate and/or scale the image of an image and store the result on the canvas.
The function needs the following parameters:
- `canvas` pointer to a canvas object to store the result of the transformation.
- `img pointer` to an image descriptor to transform. Can be the image descriptor of another canvas too (`lv_canvas_get_img()`).
@@ -70,16 +70,16 @@ The function needs the following parameters:
- `pivot_x` pivot X of rotation. Relative to the source canvas. Set to `source width / 2` to rotate around the center
- `pivot_y` pivot Y of rotation. Relative to the source canvas. Set to `source height / 2` to rotate around the center
- `antialias` true: apply anti-aliasing during the transformation. Looks better but slower.
Note that a canvas can't be rotated on itself. You need a source and destination canvas or image.
### Blur
A given area of the canvas can be blurred horizontally with `lv_canvas_blur_hor(canvas, &area, r)` or vertically with `lv_canvas_blur_ver(canvas, &area, r)`.
A given area of the canvas can be blurred horizontally with `lv_canvas_blur_hor(canvas, &area, r)` or vertically with `lv_canvas_blur_ver(canvas, &area, r)`.
`r` is the radius of the blur (greater value means more intensive burring). `area` is the area where the blur should be applied (interpreted relative to the canvas).
## Events
No special events are sent by canvas objects.
The same events are sent as for the
The same events are sent as for the
See the events of the [Images](/widgets/core/img) too.