From 3e086c2127eb51ab4c7af219cb75be5fff00bd76 Mon Sep 17 00:00:00 2001
From: Clyde Stubbs <2366188+clydebarrow@users.noreply.github.com>
Date: Tue, 4 Nov 2025 13:43:27 +1000
Subject: [PATCH] [lvgl] Fix rotation with unusual width (#11680)

---
 esphome/components/const/__init__.py          |  1 +
 esphome/components/lvgl/lvgl_esphome.cpp      | 24 ++++++++++---------
 .../components/lvgl/widgets/buttonmatrix.py   |  3 ++-
 esphome/components/matrix_keypad/__init__.py  |  3 ++-
 esphome/const.py                              |  1 -
 5 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/esphome/components/const/__init__.py b/esphome/components/const/__init__.py
index 19924f0da7..2b88bb43a8 100644
--- a/esphome/components/const/__init__.py
+++ b/esphome/components/const/__init__.py
@@ -11,4 +11,5 @@ CONF_DRAW_ROUNDING = "draw_rounding"
 CONF_ON_RECEIVE = "on_receive"
 CONF_ON_STATE_CHANGE = "on_state_change"
 CONF_REQUEST_HEADERS = "request_headers"
+CONF_ROWS = "rows"
 CONF_USE_PSRAM = "use_psram"
diff --git a/esphome/components/lvgl/lvgl_esphome.cpp b/esphome/components/lvgl/lvgl_esphome.cpp
index 947342089c..05005b0217 100644
--- a/esphome/components/lvgl/lvgl_esphome.cpp
+++ b/esphome/components/lvgl/lvgl_esphome.cpp
@@ -171,6 +171,7 @@ bool LvPageType::is_showing() const { return this->parent_->get_current_page() =
 void LvglComponent::draw_buffer_(const lv_area_t *area, lv_color_t *ptr) {
   auto width = lv_area_get_width(area);
   auto height = lv_area_get_height(area);
+  auto height_rounded = (height + this->draw_rounding - 1) / this->draw_rounding * this->draw_rounding;
   auto x1 = area->x1;
   auto y1 = area->y1;
   lv_color_t *dst = this->rotate_buf_;
@@ -178,13 +179,13 @@ void LvglComponent::draw_buffer_(const lv_area_t *area, lv_color_t *ptr) {
     case display::DISPLAY_ROTATION_90_DEGREES:
       for (lv_coord_t x = height; x-- != 0;) {
         for (lv_coord_t y = 0; y != width; y++) {
-          dst[y * height + x] = *ptr++;
+          dst[y * height_rounded + x] = *ptr++;
         }
       }
       y1 = x1;
       x1 = this->disp_drv_.ver_res - area->y1 - height;
-      width = height;
-      height = lv_area_get_width(area);
+      height = width;
+      width = height_rounded;
       break;
 
     case display::DISPLAY_ROTATION_180_DEGREES:
@@ -200,13 +201,13 @@ void LvglComponent::draw_buffer_(const lv_area_t *area, lv_color_t *ptr) {
     case display::DISPLAY_ROTATION_270_DEGREES:
       for (lv_coord_t x = 0; x != height; x++) {
         for (lv_coord_t y = width; y-- != 0;) {
-          dst[y * height + x] = *ptr++;
+          dst[y * height_rounded + x] = *ptr++;
         }
       }
       x1 = y1;
       y1 = this->disp_drv_.hor_res - area->x1 - width;
-      width = height;
-      height = lv_area_get_width(area);
+      height = width;
+      width = height_rounded;
       break;
 
     default:
@@ -443,8 +444,10 @@ LvglComponent::LvglComponent(std::vector<display::Display *> displays, float buf
 
 void LvglComponent::setup() {
   auto *display = this->displays_[0];
-  auto width = display->get_width();
-  auto height = display->get_height();
+  auto rounding = this->draw_rounding;
+  // cater for displays with dimensions that don't divide by the required rounding
+  auto width = (display->get_width() + rounding - 1) / rounding * rounding;
+  auto height = (display->get_height() + rounding - 1) / rounding * rounding;
   auto frac = this->buffer_frac_;
   if (frac == 0)
     frac = 1;
@@ -469,9 +472,8 @@ void LvglComponent::setup() {
   }
   this->buffer_frac_ = frac;
   lv_disp_draw_buf_init(&this->draw_buf_, buffer, nullptr, buffer_pixels);
-  this->disp_drv_.hor_res = width;
-  this->disp_drv_.ver_res = height;
-  // this->setup_driver_(display->get_width(), display->get_height());
+  this->disp_drv_.hor_res = display->get_width();
+  this->disp_drv_.ver_res = display->get_height();
   lv_disp_drv_update(this->disp_, &this->disp_drv_);
   this->rotation = display->get_rotation();
   if (this->rotation != display::DISPLAY_ROTATION_0_DEGREES) {
diff --git a/esphome/components/lvgl/widgets/buttonmatrix.py b/esphome/components/lvgl/widgets/buttonmatrix.py
index baeb1c8e3e..fe421aa477 100644
--- a/esphome/components/lvgl/widgets/buttonmatrix.py
+++ b/esphome/components/lvgl/widgets/buttonmatrix.py
@@ -1,8 +1,9 @@
 from esphome import automation
 import esphome.codegen as cg
+from esphome.components.const import CONF_ROWS
 from esphome.components.key_provider import KeyProvider
 import esphome.config_validation as cv
-from esphome.const import CONF_ID, CONF_ITEMS, CONF_ROWS, CONF_TEXT, CONF_WIDTH
+from esphome.const import CONF_ID, CONF_ITEMS, CONF_TEXT, CONF_WIDTH
 from esphome.cpp_generator import MockObj
 
 from ..automation import action_to_code
diff --git a/esphome/components/matrix_keypad/__init__.py b/esphome/components/matrix_keypad/__init__.py
index 2e123323a0..868b149211 100644
--- a/esphome/components/matrix_keypad/__init__.py
+++ b/esphome/components/matrix_keypad/__init__.py
@@ -1,8 +1,9 @@
 from esphome import automation, pins
 import esphome.codegen as cg
 from esphome.components import key_provider
+from esphome.components.const import CONF_ROWS
 import esphome.config_validation as cv
-from esphome.const import CONF_ID, CONF_ON_KEY, CONF_PIN, CONF_ROWS, CONF_TRIGGER_ID
+from esphome.const import CONF_ID, CONF_ON_KEY, CONF_PIN, CONF_TRIGGER_ID
 
 CODEOWNERS = ["@ssieb"]
 
diff --git a/esphome/const.py b/esphome/const.py
index 3bbc6b8b3f..d0d94ed283 100644
--- a/esphome/const.py
+++ b/esphome/const.py
@@ -838,7 +838,6 @@ CONF_RMT_CHANNEL = "rmt_channel"
 CONF_RMT_SYMBOLS = "rmt_symbols"
 CONF_ROTATION = "rotation"
 CONF_ROW = "row"
-CONF_ROWS = "rows"
 CONF_RS_PIN = "rs_pin"
 CONF_RTD_NOMINAL_RESISTANCE = "rtd_nominal_resistance"
 CONF_RTD_WIRES = "rtd_wires"