optmize line drawing

src/lv_draw/lv_draw_line.c

@@ -395,8 +395,13 @@ static void draw_line_skew(const lv_point_t * point1, const lv_point_t * point2,
 
     int16_t mask_left_id = lv_draw_mask_add(&mask_left_param, NULL);
     int16_t mask_right_id = lv_draw_mask_add(&mask_right_param, NULL);
-    int16_t mask_top_id = lv_draw_mask_add(&mask_top_param, NULL);
+    int16_t mask_top_id = LV_MASK_ID_INV;
-    int16_t mask_bottom_id = lv_draw_mask_add(&mask_bottom_param, NULL);
+    int16_t mask_bottom_id = LV_MASK_ID_INV;
+
+    if(!dsc->raw_end) {
+        mask_top_id = lv_draw_mask_add(&mask_top_param, NULL);
+        mask_bottom_id = lv_draw_mask_add(&mask_bottom_param, NULL);
+    }
 
     lv_disp_t * disp    = lv_refr_get_disp_refreshing();
     lv_disp_buf_t * vdb = lv_disp_get_buf(disp);
@@ -413,42 +418,54 @@ static void draw_line_skew(const lv_point_t * point1, const lv_point_t * point2,
      * It's easy to calculate with steep lines, but the area can be very wide with very flat lines.
      * So deal with it only with steep lines. */
     int32_t draw_area_w = lv_area_get_width(&draw_area);
-    if(!flat) draw_area_w = LV_MATH_MIN(draw_area_w, dsc->width * 2 + 2);
 
     /*Draw the background line by line*/
     int32_t h;
-    lv_opa_t * mask_buf = lv_mem_buf_get(draw_area_w);
+    size_t mask_buf_size = LV_MATH_MIN(lv_area_get_size(&draw_area), LV_HOR_RES_MAX);
+    lv_opa_t * mask_buf = lv_mem_buf_get(mask_buf_size);
+
     lv_area_t fill_area;
     fill_area.x1 = draw_area.x1 + disp_area->x1;
     fill_area.x2 = draw_area.x2 + disp_area->x1;
     fill_area.y1 = draw_area.y1 + disp_area->y1;
     fill_area.y2 = fill_area.y1;
 
-    lv_point_t v;
-    v.x = p2.x - p1.x;
-    v.y = p2.y - p1.y;
     int32_t x = vdb->area.x1 + draw_area.x1;
 
+    uint32_t mask_p = 0;
+
+    lv_memset_ff(mask_buf, mask_buf_size);
     /*Fill the first row with 'color'*/
     for(h = draw_area.y1 + disp_area->y1; h <= draw_area.y2 + disp_area->y1; h++) {
-        lv_memset_ff(mask_buf, draw_area_w);
 
-        if(!flat) {
+        lv_draw_mask_res_t mask_res = lv_draw_mask_apply(&mask_buf[mask_p], x, h, draw_area_w);
-            /*Where is the current point?*/
+        if(mask_res == LV_DRAW_MASK_RES_FULL_TRANSP) {
-            x = (v.y * p1.x - v.x * p1.y + v.x * h) / v.y - dsc->width - 1;
+            lv_memset_00(&mask_buf[mask_p], draw_area_w);
-            if(x < draw_area.x1 + disp_area->x1) x = draw_area.x1 + disp_area->x1;
-            fill_area.x1 = x;
-            fill_area.x2 = fill_area.x1 + draw_area_w - 1;
         }
 
-        lv_draw_mask_res_t mask_res = lv_draw_mask_apply(mask_buf, x, h, draw_area_w);
+        mask_p += draw_area_w;
+        if((uint32_t) mask_p + draw_area_w < mask_buf_size) {
+            fill_area.y2 ++;
+        }
+        else {
+            lv_blend_fill(&fill_area, clip,
+                    dsc->color, mask_buf, LV_DRAW_MASK_RES_CHANGED, dsc->opa,
+                    dsc->blend_mode);
 
-        lv_blend_fill(clip, &fill_area,
+            fill_area.y1 = fill_area.y2 + 1;
-                      dsc->color, mask_buf, mask_res, opa,
+            fill_area.y2 = fill_area.y1;
-                      dsc->blend_mode);
+            mask_p = 0;
+            lv_memset_ff(mask_buf, mask_buf_size);
+        }
+    }
+
+    /*Flush the last part*/
+    if(fill_area.y1 != fill_area.y2) {
+        fill_area.y2--;
+        lv_blend_fill( &fill_area, clip,
+                dsc->color, mask_buf, LV_DRAW_MASK_RES_CHANGED, dsc->opa,
+                dsc->blend_mode);
 
-        fill_area.y1++;
-        fill_area.y2++;
     }
 
     lv_mem_buf_release(mask_buf);

src/lv_draw/lv_draw_line.h

@@ -31,6 +31,7 @@ typedef struct {
     lv_blend_mode_t blend_mode  : 2;
     uint8_t round_start : 1;
     uint8_t round_end   : 1;
+    uint8_t raw_end     : 1;    /*Do not bother with perpendicular line ending is it's not visible for any reason*/
 } lv_draw_line_dsc_t;
 
 /**********************

src/lv_widgets/lv_linemeter.c

@@ -55,17 +55,17 @@ lv_obj_t * lv_linemeter_create(lv_obj_t * par, const lv_obj_t * copy)
     LV_LOG_TRACE("line meter create started");
 
     /*Create the ancestor of line meter*/
-    lv_obj_t * new_lmeter = lv_obj_create(par, copy);
+    lv_obj_t * linemeter = lv_obj_create(par, copy);
-    LV_ASSERT_MEM(new_lmeter);
+    LV_ASSERT_MEM(linemeter);
-    if(new_lmeter == NULL) return NULL;
+    if(linemeter == NULL) return NULL;
 
-    if(ancestor_signal == NULL) ancestor_signal = lv_obj_get_signal_cb(new_lmeter);
+    if(ancestor_signal == NULL) ancestor_signal = lv_obj_get_signal_cb(linemeter);
 
     /*Allocate the line meter type specific extended data*/
-    lv_linemeter_ext_t * ext = lv_obj_allocate_ext_attr(new_lmeter, sizeof(lv_linemeter_ext_t));
+    lv_linemeter_ext_t * ext = lv_obj_allocate_ext_attr(linemeter, sizeof(lv_linemeter_ext_t));
     LV_ASSERT_MEM(ext);
     if(ext == NULL) {
-        lv_obj_del(new_lmeter);
+        lv_obj_del(linemeter);
         return NULL;
     }
 
@@ -78,13 +78,13 @@ lv_obj_t * lv_linemeter_create(lv_obj_t * par, const lv_obj_t * copy)
     ext->angle_ofs = 0;
 
     /*The signal and design functions are not copied so set them here*/
-    lv_obj_set_signal_cb(new_lmeter, lv_linemeter_signal);
+    lv_obj_set_signal_cb(linemeter, lv_linemeter_signal);
-    lv_obj_set_design_cb(new_lmeter, lv_linemeter_design);
+    lv_obj_set_design_cb(linemeter, lv_linemeter_design);
 
     /*Init the new line meter line meter*/
     if(copy == NULL) {
-        lv_obj_set_size(new_lmeter, LV_DPI, LV_DPI);
+        lv_obj_set_size(linemeter, LV_DPI, LV_DPI);
-        lv_theme_apply(new_lmeter, LV_THEME_LINEMETER);
+        lv_theme_apply(linemeter, LV_THEME_LINEMETER);
     }
     /*Copy an existing line meter*/
     else {
@@ -95,13 +95,13 @@ lv_obj_t * lv_linemeter_create(lv_obj_t * par, const lv_obj_t * copy)
         ext->max_value             = copy_ext->max_value;
         ext->cur_value             = copy_ext->cur_value;
 
-        //        /*Refresh the style with new signal function*/
+        /*Refresh the style with new signal function*/
-        //        lv_obj_refresh_style(new_lmeter);
+        lv_obj_refresh_style(linemeter, LV_STYLE_PROP_ALL);
     }
 
     LV_LOG_INFO("line meter created");
 
-    return new_lmeter;
+    return linemeter;
 }
 
 /*=====================
@@ -293,6 +293,7 @@ void lv_linemeter_draw_scale(lv_obj_t * lmeter, const lv_area_t * clip_area, uin
     lv_draw_line_dsc_t line_dsc;
     lv_draw_line_dsc_init(&line_dsc);
     lv_obj_init_draw_line_dsc(lmeter, part, &line_dsc);
+    line_dsc.raw_end = 1;
 
     lv_style_int_t end_line_width = lv_obj_get_style_scale_end_line_width(lmeter, part);