feat(style) add support for declaring styles in ROM (#2220)

Co-authored-by: Gabor Kiss-Vamosi <kisvegabor@gmail.com>

scripts/style_api_gen.py

@@ -388,6 +388,17 @@ def local_style_set(p):
   print("}")
   print("")
 
+def style_const_set(p):
+    cast = style_set_cast(p['style_type'])
+    print("#define LV_STYLE_CONST_" + p['name'] + "(val) \\")
+    print("    { \\")
+    print("        .prop = LV_STYLE_" + p['name'] + ", \\")
+    print("        .value = { \\")
+    print("            ." + p['style_type'] +" = " + cast + "val \\")
+    print("        } \\")
+    print("    }")
+    print("")
+
 
 
 def docs(p):
@@ -430,6 +441,7 @@ sys.stdout = open(base_dir + '/../src/misc/lv_style_gen.h', 'w')
 
 for p in props:
   style_set(p)
+  style_const_set(p)
   
 sys.stdout = open(base_dir + '/style_props.md', 'w')
   

src/misc/lv_style.c

@@ -55,6 +55,11 @@ void lv_style_reset(lv_style_t * style)
 {
     LV_ASSERT_STYLE(style);
 
+    if(style->is_const) {
+        LV_LOG_ERROR("Cannot reset const style");
+        return;
+    }
+
     if(style->prop_cnt > 1) lv_mem_free(style->v_p.values_and_props);
     lv_memset_00(style, sizeof(lv_style_t));
 #if LV_USE_ASSERT_STYLE
@@ -74,6 +79,11 @@ bool lv_style_remove_prop(lv_style_t * style, lv_style_prop_t prop)
 {
     LV_ASSERT_STYLE(style);
 
+    if(style->is_const) {
+        LV_LOG_ERROR("Cannot remove prop from const style");
+        return false;
+    }
+
     if(style->prop_cnt == 0)  return false;
 
     if(style->prop_cnt == 1) {
@@ -92,10 +102,11 @@ bool lv_style_remove_prop(lv_style_t * style, lv_style_prop_t prop)
         if(old_props[i] == prop) {
             lv_style_value_t * old_values = (lv_style_value_t *)style->v_p.values_and_props;
 
-            uint16_t * new_props = &style->prop1;
-            lv_style_value_t * new_values = &style->v_p.value1;
-
-            if(style->prop_cnt > 2) {
+            if(style->prop_cnt == 2) {
+                style->prop_cnt = 1;
+                style->prop1 = i == 0 ? old_props[1] : old_props[0];
+                style->v_p.value1 = i == 0 ? old_values[1] : old_values[0];
+            } else {
                 size_t size = (style->prop_cnt - 1) * (sizeof(lv_style_value_t) + sizeof(uint16_t));
                 uint8_t * new_values_and_props = lv_mem_alloc(size);
                 if(new_values_and_props == NULL) return false;
@@ -103,19 +114,15 @@ bool lv_style_remove_prop(lv_style_t * style, lv_style_prop_t prop)
                 style->prop_cnt--;
 
                 tmp = new_values_and_props + style->prop_cnt * sizeof(lv_style_value_t);
-                new_props = (uint16_t *)tmp;
-                new_values = (lv_style_value_t *)new_values_and_props;
-            } else {
-                style->prop_cnt = 1;
-                style->prop1 = i == 0 ? old_props[1] : old_props[0];
-                style->v_p.value1 = i == 0 ? old_values[1] : old_values[0];
-            }
+                uint16_t * new_props = (uint16_t *)tmp;
+                lv_style_value_t * new_values = (lv_style_value_t *)new_values_and_props;
 
-            uint32_t j;
-            for(i = j = 0; j <= style->prop_cnt; j++) { /*<=: because prop_cnt already reduced but all the old props. needs to be checked.*/
-                if(old_props[j] != prop) {
-                    new_values[i] = old_values[j];
-                    new_props[i++] = old_props[j];
+                uint32_t j;
+                for(i = j = 0; j <= style->prop_cnt; j++) { /*<=: because prop_cnt already reduced but all the old props. needs to be checked.*/
+                    if(old_props[j] != prop) {
+                        new_values[i] = old_values[j];
+                        new_props[i++] = old_props[j];
+                    }
                 }
             }
 
@@ -131,6 +138,11 @@ void lv_style_set_prop(lv_style_t * style, lv_style_prop_t prop, lv_style_value_
 {
     LV_ASSERT_STYLE(style);
 
+    if(style->is_const) {
+        LV_LOG_ERROR("Cannot set property of constant style");
+        return;
+    }
+
     if(style->prop_cnt > 1) {
         uint8_t * tmp = style->v_p.values_and_props + style->prop_cnt * sizeof(lv_style_value_t);
         uint16_t * props = (uint16_t *)tmp;

src/misc/lv_style.h

@@ -43,6 +43,12 @@ extern "C" {
 #define LV_IMG_ZOOM_NONE            256        /*Value for not zooming the image*/
 LV_EXPORT_CONST_INT(LV_IMG_ZOOM_NONE);
 
+#if LV_USE_ASSERT_STYLE
+#define LV_STYLE_CONST_INIT(var_name, prop_array) const lv_style_t var_name = { .sentinel = LV_STYLE_SENTINEL_VALUE, .v_p = { .const_props = prop_array }, .has_group = 0xFF, .is_const = 1 }
+#else
+#define LV_STYLE_CONST_INIT(var_name, prop_array) const lv_style_t var_name = { .v_p = { .const_props = prop_array }, .has_group = 0xFF, .is_const = 1 }
+#endif
+
 /**********************
  *      TYPEDEFS
  **********************/
@@ -236,6 +242,14 @@ typedef struct _lv_style_transiton_t {
     uint32_t delay;                /**< Delay before the transition in [ms]*/
 }lv_style_transition_dsc_t;
 
+
+/**
+ * Descriptor of a constant style property.
+ */
+typedef struct {
+    lv_style_prop_t prop;
+    lv_style_value_t value;
+} lv_style_const_prop_t;
 /**
  * Descriptor of a style (a collection of properties and values).
  */
@@ -250,9 +264,11 @@ typedef struct {
     union {
         lv_style_value_t value1;
         uint8_t * values_and_props;
+        const lv_style_const_prop_t * const_props;
     } v_p;
 
-    uint16_t prop1;
+    uint16_t prop1 :15;
+    uint16_t is_const :1;
     uint8_t has_group;
     uint8_t prop_cnt;
 } lv_style_t;
@@ -334,6 +350,17 @@ lv_res_t lv_style_get_prop(lv_style_t * style, lv_style_prop_t prop, lv_style_va
  */
 static inline lv_res_t lv_style_get_prop_inlined(lv_style_t * style, lv_style_prop_t prop, lv_style_value_t * value)
 {
+    if(style->is_const) {
+        const lv_style_const_prop_t *const_prop;
+        for(const_prop = style->v_p.const_props; const_prop->prop != LV_STYLE_PROP_INV; const_prop++) {
+            if(const_prop->prop == prop) {
+                *value = const_prop->value;
+                return LV_RES_OK;
+            }
+        }
+        return LV_RES_INV;
+    }
+
     if(style->prop_cnt == 0) return LV_RES_INV;
 
     if(style->prop_cnt > 1) {