add textbox:lineAt and textbox:linePos

src/graphics/ui/elements/TextBox.cpp

@@ -623,6 +623,14 @@ void TextBox::select(int start, int end) {
     setCaret(selectionEnd);
 }
 
+uint TextBox::getLineAt(size_t position) const {
+    return label->getLineByTextIndex(position);
+}
+
+size_t TextBox::getLinePos(uint line) const {
+    return label->getTextLineOffset(line);
+}
+
 std::shared_ptr<UINode> TextBox::getAt(glm::vec2 pos, std::shared_ptr<UINode> self) {
     return UINode::getAt(pos, self);
 }
@@ -740,7 +748,7 @@ void TextBox::setCaret(size_t position) {
     uint lineHeight = font->getLineHeight()*label->getLineInterval();
     scrollStep = lineHeight;
     if (offset < 0) {
-        scrolled(1);
+        scrolled(-glm::floor(offset/static_cast<double>(scrollStep)+0.5f));
     } else if (offset >= getSize().y) {
         offset -= getSize().y;
         scrolled(-glm::ceil(offset/static_cast<double>(scrollStep)+0.5f));

src/graphics/ui/elements/TextBox.hpp

@@ -159,6 +159,16 @@ namespace gui {
         /// @param end index of the last selected character + 1
         virtual void select(int start, int end);
 
+        /// @brief Get number of line at specific position in text
+        /// @param position target position
+        /// @return line number
+        virtual uint getLineAt(size_t position) const;
+
+        /// @brief Get specific line text position
+        /// @param line target line
+        /// @return line position in text
+        virtual size_t getLinePos(uint line) const;
+
         /// @brief Check text with validator set with setTextValidator
         /// @return true if text is valid
         virtual bool validate();

src/logic/scripting/lua/libs/libgui.cpp

@@ -134,6 +134,24 @@ static int l_move_into(lua::State* L) {
     return 0;
 }
 
+static int l_get_line_at(lua::State* L) {
+    auto node = getDocumentNode(L, 1);
+    auto position = lua::tointeger(L, 2);
+    if (auto box = dynamic_cast<TextBox*>(node.node.get())) {
+        return lua::pushinteger(L, box->getLineAt(position));
+    }
+    return 0;
+}
+
+static int l_get_line_pos(lua::State* L) {
+    auto node = getDocumentNode(L, 1);
+    auto line = lua::tointeger(L, 2);
+    if (auto box = dynamic_cast<TextBox*>(node.node.get())) {
+        return lua::pushinteger(L, box->getLinePos(line));
+    }
+    return 0;
+}
+
 static int p_get_inventory(UINode* node, lua::State* L) {
     if (auto inventory = dynamic_cast<InventoryView*>(node)) {
         auto inv = inventory->getInventory();
@@ -356,6 +374,12 @@ static int p_move_into(UINode*, lua::State* L) {
 static int p_get_focused(UINode* node, lua::State* L) {
     return lua::pushboolean(L, node->isFocused());
 }
+static int p_get_line_at(UINode*, lua::State* L) {
+    return lua::pushcfunction(L, l_get_line_at);
+}
+static int p_get_line_pos(UINode*, lua::State* L) {
+    return lua::pushcfunction(L, l_get_line_pos);
+}
 
 static int l_gui_getattr(lua::State* L) {
     auto docname = lua::require_string(L, 1);
@@ -391,6 +415,8 @@ static int l_gui_getattr(lua::State* L) {
             {"text", p_get_text},
             {"editable", p_get_editable},
             {"lineNumbers", p_get_line_numbers},
+            {"lineAt", p_get_line_at},
+            {"linePos", p_get_line_pos},
             {"src", p_get_src},
             {"value", p_get_value},
             {"min", p_get_min},