Embedded/lvgl
1
0
Fork 0
mirror of https://github.com/lvgl/lvgl.git synced 2025-01-28 07:03:00 +08:00
Code Issues Projects Releases Wiki Activity

improve arc draw accuracy

Browse Source
This commit is contained in:
Gabor Kiss-Vamosi 2019-11-27 11:45:38 +01:00
parent 23a040670e
commit 74fe37ba5b
1 changed files with 68 additions and 29 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

97
src/lv_draw/lv_draw_arc.c
View File

@ -8,7 +8,7 @@
*********************/
#include "lv_draw_arc.h"
#include "lv_draw_mask.h"
#include "../lv_misc/lv_math.h" // LV_TRIGO_SHIFT
#include "../lv_misc/lv_math.h"
/*********************
* DEFINES
@ -21,6 +21,7 @@
/**********************
* STATIC PROTOTYPES
**********************/
static void get_rounded_area(int16_t angle, lv_coord_t radius, uint8_t tickness, lv_area_t * res_area);
/**********************
* STATIC VARIABLES
@ -46,7 +47,7 @@
* @param opa_scale scale down all opacities by the factor
*/
void lv_draw_arc(lv_coord_t center_x, lv_coord_t center_y, uint16_t radius, const lv_area_t * clip_area,
uint16_t start_angle, uint16_t end_angle, const lv_style_t * style, lv_opa_t opa_scale)
uint16_t start_angle, uint16_t end_angle, const lv_style_t * style, lv_opa_t opa_scale)
{
lv_style_t circle_style;
lv_style_copy(&circle_style, style);
@ -64,40 +65,35 @@ void lv_draw_arc(lv_coord_t center_x, lv_coord_t center_y, uint16_t radius, cons
lv_area_t area;
area.x1 = center_x - radius;
area.y1 = center_y - radius;
area.x2 = center_x + radius;
area.y2 = center_y + radius;
area.x2 = center_x + radius - 1; /*-1 because the center already belongs to the left/bottom part*/
area.y2 = center_y + radius - 1;
lv_draw_rect(&area, clip_area, &circle_style, LV_OPA_COVER);
lv_draw_mask_remove_id(mask_angle_id);
if(style->line.rounded) {
circle_style.body.main_color = style->line.color;
circle_style.body.grad_color = style->line.color;
circle_style.body.opa = LV_OPA_COVER;
circle_style.body.border.width = 0;
circle_style.body.main_color = style->line.color;
circle_style.body.grad_color = style->line.color;
circle_style.body.opa = LV_OPA_COVER;
circle_style.body.border.width = 0;
lv_coord_t thick_half = style->line.width / 2;
lv_coord_t cir_x = ((radius - thick_half + 1) * lv_trigo_sin(90 - start_angle) >> LV_TRIGO_SHIFT);
lv_coord_t cir_y = ((radius - thick_half + 1) * lv_trigo_sin(start_angle) >> LV_TRIGO_SHIFT);
lv_area_t round_area;
round_area.x1 = cir_x + center_x - thick_half + 1;
round_area.y1 = cir_y + center_y - thick_half + 1;
round_area.x2 = cir_x + center_x + thick_half;
round_area.y2 = cir_y + center_y + thick_half;
lv_draw_rect(&round_area, clip_area, &circle_style, LV_OPA_COVER);
cir_x = ((radius - thick_half + 1) * lv_trigo_sin(90 - end_angle) >> LV_TRIGO_SHIFT);
cir_y = ((radius - thick_half + 1) * lv_trigo_sin(end_angle) >> LV_TRIGO_SHIFT);
round_area.x1 = cir_x + center_x - thick_half + 1;
round_area.y1 = cir_y + center_y - thick_half + 1;
round_area.x2 = cir_x + center_x + thick_half;
round_area.y2 = cir_y + center_y + thick_half;
lv_draw_rect(&round_area, clip_area, &circle_style, LV_OPA_COVER);
lv_area_t round_area;
get_rounded_area(start_angle, radius, style->line.width, &round_area);
round_area.x1 += center_x;
round_area.x2 += center_x;
round_area.y1 += center_y;
round_area.y2 += center_y;
lv_draw_rect(&round_area, clip_area, &circle_style, opa_scale);
get_rounded_area(end_angle, radius, style->line.width, &round_area);
round_area.x1 += center_x;
round_area.x2 += center_x;
round_area.y1 += center_y;
round_area.y2 += center_y;
lv_draw_rect(&round_area, clip_area, &circle_style, opa_scale);
}
}
@ -106,3 +102,46 @@ void lv_draw_arc(lv_coord_t center_x, lv_coord_t center_y, uint16_t radius, cons
* STATIC FUNCTIONS
**********************/
static void get_rounded_area(int16_t angle, lv_coord_t radius, uint8_t tickness, lv_area_t * res_area)
{
lv_coord_t thick_half = tickness / 2;
lv_coord_t thick_corr = tickness & 0x01 ? 0 : 1;
lv_coord_t rx_corr;
lv_coord_t ry_corr;
if(angle > 90 && angle < 270) rx_corr = 0;
else rx_corr = 0;
if(angle > 0 && angle < 180) ry_corr = 0;
else ry_corr = 0;
lv_coord_t cir_x;
lv_coord_t cir_y;
cir_x = ((radius - rx_corr - thick_half) * lv_trigo_sin(90 - angle)) >> (LV_TRIGO_SHIFT - 4);
cir_y = ((radius - ry_corr - thick_half) * lv_trigo_sin(angle)) >> (LV_TRIGO_SHIFT - 4);
/* Actually the center of the pixel need to be calculated so apply 1/2 px offset*/
if(cir_x > 0) {
cir_x = (cir_x - 8) >> 4;
res_area->x1 = cir_x - thick_half + thick_corr;
res_area->x2 = cir_x + thick_half;
}
else {
cir_x = (cir_x + 2) >> 4;
res_area->x1 = cir_x - thick_half;
res_area->x2 = cir_x + thick_half - thick_corr;
}
if(cir_y > 0) {
cir_y = (cir_y - 8) >> 4;
res_area->y1 = cir_y - thick_half + thick_corr;
res_area->y2 = cir_y + thick_half;
}
else {
cir_y = (cir_y + 8) >> 4;
res_area->y1 = cir_y - thick_half;
res_area->y2 = cir_y + thick_half - thick_corr;
}
}