lv_draw_arc.h

Functions

void lv_draw_arc_dsc_init(lv_draw_arc_dsc_t *dsc)

Initialize an arc draw descriptor.

参数:

dsc -- pointer to a draw descriptor

lv_draw_arc_dsc_t *lv_draw_task_get_arc_dsc(lv_draw_task_t *task)

Try to get an arc draw descriptor from a draw task.

参数:

task -- draw task

返回:

the task's draw descriptor or NULL if the task is not of type LV_DRAW_TASK_TYPE_ARC

void lv_draw_arc(lv_layer_t *layer, const lv_draw_arc_dsc_t *dsc)

Create an arc draw task.

参数:

  • layer -- pointer to a layer

  • dsc -- pointer to an initialized draw descriptor variable

void lv_draw_arc_get_area(int32_t x, int32_t y, uint16_t radius, lv_value_precise_t start_angle, lv_value_precise_t end_angle, int32_t w, bool rounded, lv_area_t *area)

Get an area the should be invalidated when the arcs angle changed between start_angle and end_ange

参数:

  • x -- the x coordinate of the center of the arc

  • y -- the y coordinate of the center of the arc

  • radius -- the radius of the arc

  • start_angle -- the start angle of the arc (0 deg on the bottom, 90 deg on the right)

  • end_angle -- the end angle of the arc

  • w -- width of the arc

  • rounded -- true: the arc is rounded

  • area -- store the area to invalidate here

struct lv_draw_arc_dsc_t

Public Members

lv_draw_dsc_base_t base
lv_color_t color
int32_t width
lv_value_precise_t start_angle
lv_value_precise_t end_angle
lv_point_t center
uint16_t radius
const void *img_src
lv_opa_t opa
uint8_t rounded