Optimize LVGL rendering performance, disable DMA, add PNG/BMP/GIF support

platformio.ini

@@ -32,7 +32,7 @@ build_flags =
 	-DLV_USE_FS_STDIO=0
 	-DLV_USE_FS_POSIX=0
 	-DLV_USE_IME_PINYIN=1
-	-DLVGL_DRAW_BUF_DIV=4
+	-DLVGL_DRAW_BUF_DIV=2
 	-DLVGL_DOUBLE_BUF=1
 	-DLV_MEM_POOL_SIZE_KB=384
 	-DCORE_DEBUG_LEVEL=0
@@ -42,7 +42,7 @@ build_flags =
 	-DARDUINO_LOOP_STACK_SIZE=16384
 	-DBOARD_HAS_PSRAM
 	-mfix-esp32-psram-cache-issue
-	-Os
+	-O2
 lib_deps = 
 	bodmer/TFT_eSPI@^2.5.43
 	https://github.com/PaulStoffregen/XPT2046_Touchscreen.git#v1.4

src/Setup_ESP32_2432S028R_ILI9341.h

@@ -365,7 +365,7 @@
 // #define SPI_FREQUENCY  10000000
 // #define SPI_FREQUENCY  20000000
 // #define SPI_FREQUENCY  27000000
-#define SPI_FREQUENCY  55000000
+#define SPI_FREQUENCY  80000000
 // #define SPI_FREQUENCY  55000000
 // #define SPI_FREQUENCY  80000000
 
@@ -380,8 +380,8 @@
 // then uncomment the following line:
 #define USE_HSPI_PORT
 
-// Enable TFT_eSPI DMA path on classic ESP32 to improve flush throughput.
-#define ESP32_DMA
+// DMA disabled: causes screen corruption on this hardware.
+// #define ESP32_DMA
 
 // Comment out the following #define if "SPI Transactions" do not need to be
 // supported. When commented out the code size will be smaller and sketches will

src/app.h

@@ -283,10 +283,12 @@ class AppManager {
         if (bytes_read == 0 && read_chunk_file_size > 0) return false;
 
         read_chunk_bytes = bytes_read;
+        bool has_prev = read_chunk_index > 0;
+        bool has_next = ((uint64_t)offset + (uint64_t)read_chunk_bytes) < read_chunk_file_size;
+
         editor.setTitle(current_filename);
         editor.setReadChunkMode(true);
-        editor.setReadChunkNavigationState(read_chunk_index > 0, ((uint64_t)offset + (uint64_t)read_chunk_bytes) < read_chunk_file_size);
-        editor.setReadChunkText(content, anchor_end);
+        editor.setReadChunkText(content, has_prev, has_next, anchor_end);
         return true;
     }
 
@@ -512,7 +514,7 @@ class AppManager {
         if (dot < 0) return false;
         String ext = path.substring(dot + 1);
         ext.toLowerCase();
-        return (ext == "jpg" || ext == "jpeg");
+        return (ext == "jpg" || ext == "jpeg" || ext == "png" || ext == "bmp" || ext == "gif");
     }
 
     void showPrevImage() {

src/lv_conf.h

@@ -144,7 +144,7 @@
  * and can't be drawn in chunks. */
 
 /*The target buffer size for simple layer chunks.*/
-#define LV_DRAW_LAYER_SIMPLE_BUF_SIZE    (12 * 1024)   /*[bytes]*/
+#define LV_DRAW_LAYER_SIMPLE_BUF_SIZE    (24 * 1024)   /*[bytes]*/
 
 /* The stack size of the drawing thread.
  * NOTE: If FreeType or ThorVG is enabled, it is recommended to set it to 32KB or more.
@@ -190,13 +190,13 @@
         /*Allow buffering some shadow calculation.
         *LV_DRAW_SW_SHADOW_CACHE_SIZE is the max. shadow size to buffer, where shadow size is `shadow_width + radius`
         *Caching has LV_DRAW_SW_SHADOW_CACHE_SIZE^2 RAM cost*/
-        #define LV_DRAW_SW_SHADOW_CACHE_SIZE 0
+        #define LV_DRAW_SW_SHADOW_CACHE_SIZE 128
 
         /* Set number of maximally cached circle data.
         * The circumference of 1/4 circle are saved for anti-aliasing
         * radius * 4 bytes are used per circle (the most often used radiuses are saved)
         * 0: to disable caching */
-        #define LV_DRAW_SW_CIRCLE_CACHE_SIZE 4
+        #define LV_DRAW_SW_CIRCLE_CACHE_SIZE 32
     #endif
 
     #define  LV_USE_DRAW_SW_ASM     LV_DRAW_SW_ASM_NONE
@@ -381,11 +381,11 @@
  *Used by image decoders such as `lv_lodepng` to keep the decoded image in the memory.
  *If size is not set to 0, the decoder will fail to decode when the cache is full.
  *If size is 0, the cache function is not enabled and the decoded mem will be released immediately after use.*/
-#define LV_CACHE_DEF_SIZE       0
+#define LV_CACHE_DEF_SIZE       (64 * 1024)
 
 /*Default number of image header cache entries. The cache is used to store the headers of images
  *The main logic is like `LV_CACHE_DEF_SIZE` but for image headers.*/
-#define LV_IMAGE_HEADER_CACHE_DEF_CNT 0
+#define LV_IMAGE_HEADER_CACHE_DEF_CNT 8
 
 /*Number of stops allowed per gradient. Increase this to allow more stops.
  *This adds (sizeof(lv_color_t) + 1) bytes per additional stop*/
@@ -396,7 +396,7 @@
 #define LV_COLOR_MIX_ROUND_OFS  0
 
 /* Add 2 x 32 bit variables to each lv_obj_t to speed up getting style properties */
-#define LV_OBJ_STYLE_CACHE      0
+#define LV_OBJ_STYLE_CACHE      1
 
 /* Add `id` field to `lv_obj_t` */
 #define LV_USE_OBJ_ID           0
@@ -703,8 +703,8 @@
     /*0: Light mode; 1: Dark mode*/
     #define LV_THEME_DEFAULT_DARK 0
 
-    /*1: Enable grow on press*/
-    #define LV_THEME_DEFAULT_GROW 1
+    /*0: Disable grow on press to eliminate extra redraw area during press animations*/
+    #define LV_THEME_DEFAULT_GROW 0
 
     /*Default transition time in [ms]*/
     #define LV_THEME_DEFAULT_TRANSITION_TIME 80
@@ -791,13 +791,13 @@
 #endif
 
 /*LODEPNG decoder library*/
-#define LV_USE_LODEPNG 0
+#define LV_USE_LODEPNG 1
 
 /*PNG decoder(libpng) library*/
 #define LV_USE_LIBPNG 0
 
 /*BMP decoder library*/
-#define LV_USE_BMP 0
+#define LV_USE_BMP 1
 
 /* JPG + split JPG decoder library.
  * Split JPG is a custom format optimized for embedded systems. */
@@ -808,7 +808,7 @@
 #define LV_USE_LIBJPEG_TURBO 0
 
 /*GIF decoder library*/
-#define LV_USE_GIF 0
+#define LV_USE_GIF 1
 #if LV_USE_GIF
     /*GIF decoder accelerate*/
     #define LV_GIF_CACHE_DECODE_DATA 0

src/ui/editor.h

@@ -20,6 +20,7 @@ class Editor {
     static constexpr uint8_t IME_CAND_PER_PAGE = 8;
     static constexpr uint16_t IME_CAND_MAX = 160;
     static constexpr size_t LARGE_DOC_PERF_THRESHOLD = 2 * 1024;
+    static constexpr int32_t TEXTAREA_SCROLL_ANIM_MS = 260;
     static constexpr int32_t CHUNK_NAV_BTN_SIZE = 24;
     static constexpr lv_opa_t CHUNK_NAV_BTN_BG_OPA = static_cast<lv_opa_t>((LV_OPA_COVER * 75) / 100);
     lv_obj_t* screen;
@@ -199,7 +200,7 @@ class Editor {
         lv_obj_set_style_width(textarea, 1, LV_PART_CURSOR);
         lv_obj_add_flag(textarea, LV_OBJ_FLAG_SCROLL_ELASTIC);
         lv_obj_add_flag(textarea, LV_OBJ_FLAG_SCROLL_MOMENTUM);
-        lv_obj_set_style_anim_duration(textarea, 260, 0);
+        lv_obj_set_style_anim_duration(textarea, TEXTAREA_SCROLL_ANIM_MS, 0);
         int32_t editor_cursor_h = EDITOR_TEXT_SIZE_PX;
         if (editor_cursor_h < 2) editor_cursor_h = 2;
         lv_obj_set_style_height(textarea, editor_cursor_h, LV_PART_CURSOR);
@@ -365,12 +366,50 @@ class Editor {
         refreshReadChunkButtons();
     }
 
-    void setReadChunkText(const String& content, bool anchor_end) {
+    void setReadChunkText(const String& content, bool has_prev, bool has_next, bool anchor_end) {
         if (!textarea) return;
+
+        // Suppress scroll animations during content swap so that the
+        // internal auto-scroll triggered by lv_textarea_set_text() does
+        // not conflict with the explicit scroll below.  This is the root
+        // cause of the visible "scroll-up jump" on every chunk switch.
+        lv_obj_set_style_anim_duration(textarea, 0, 0);
+
         applyLargeDocPerfMode(content.length());
+
+        // Batch-update navigation state before the final button refresh.
+        read_chunk_has_prev = has_prev;
+        read_chunk_has_next = has_next;
+
+        // Replace content.  LVGL internally moves the cursor to the end
+        // of the new text and auto-scrolls, but with anim_duration == 0
+        // the scroll is instantaneous and invisible.
         lv_textarea_set_text(textarea, content.c_str());
-        if (anchor_end) moveCursorAndViewToEnd();
-        else moveCursorAndViewToStart();
+
+        // Set cursor and record anchor for IME.
+        if (anchor_end) {
+            uint32_t len = (uint32_t)content.length();
+            lv_textarea_set_cursor_pos(textarea, (int32_t)len);
+            ime_cursor_anchor_pos = len;
+        } else {
+            lv_textarea_set_cursor_pos(textarea, 0);
+            ime_cursor_anchor_pos = 0;
+        }
+        ime_cursor_anchor_valid = true;
+
+        // Force layout so scroll metrics are accurate, then set the
+        // definitive scroll position in one shot.
+        lv_obj_update_layout(textarea);
+        if (anchor_end) {
+            int32_t bottom = lv_obj_get_scroll_bottom(textarea);
+            if (bottom > 0) lv_obj_scroll_by(textarea, 0, bottom, LV_ANIM_OFF);
+        } else {
+            lv_obj_scroll_to_y(textarea, 0, LV_ANIM_OFF);
+        }
+
+        // Restore normal scroll animation for user interaction.
+        lv_obj_set_style_anim_duration(textarea, TEXTAREA_SCROLL_ANIM_MS, 0);
+
         clearReadChunkFocus();
         refreshReadChunkButtons();
     }