preliminary tft state tracking

main/drivers/tft.cpp

@@ -1,4 +1,5 @@
 #include "tft.h"
+#include "state_tracking.h"
 
 static const char* TAG = "tft";
 
@@ -26,6 +27,14 @@ static bool notify_lvgl_flush_ready(
     return false;
 }
 
+const char base64_chars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+/// Base 64 encodes a u16... sort of. This doesn't do any of the fancy padding stuff.
+static void encode_base64(char* buf, size_t start_idx, uint16_t value) {
+    buf[start_idx+0] = base64_chars[(value >> 10) & 0x3F];
+    buf[start_idx+1] = base64_chars[(value >> 4) & 0x3F];
+    buf[start_idx+2] = base64_chars[(value << 2) & 0x3F];
+}
+
 static void lvgl_flush_cb(lv_disp_drv_t *drv, const lv_area_t *area, lv_color_t *color_map) {
     esp_lcd_panel_handle_t panel_handle = (esp_lcd_panel_handle_t) drv->user_data;
 
@@ -33,7 +42,46 @@ static void lvgl_flush_cb(lv_disp_drv_t *drv, const lv_area_t *area, lv_color_t
     int offsetx2 = area->x2;
     int offsety1 = area->y1;
     int offsety2 = area->y2;
+
     esp_lcd_panel_draw_bitmap(panel_handle, offsetx1, offsety1, offsetx2 + 1, offsety2 + 1, color_map);
+
+    // TODO: change this to be a kconfig value
+    #if true
+
+    if (is_state_tracking()) {
+        size_t size = (offsetx2 + 1 - offsetx1) * (offsety2 + 1 - offsety1) + 1;
+        // if (size > 1024) {
+        //     ESP_LOGW("tft_track_state", "Write too big (%d)! truncating to 1024!", size);
+        // }
+        // size = MIN(1024, size);
+
+
+        // 24 bytes for the offsets
+        // 3 bytes per encoded color
+        // 1 byte for null terminator
+        size_t alloc_size = 24 + size * 3 + 1;
+        char* buf = (char*)malloc(alloc_size);
+
+        if (buf != nullptr) {
+            size_t initial_offset = sprintf(buf, "%d,%d,%d,%d:", offsetx1, offsety1, offsetx2 + 1, offsety2 + 1);
+
+            for (size_t i = 0; i < size; i++) {
+                size_t index = initial_offset + i * 3;
+
+                // we assume that the size of the color data is 16b
+                static_assert(sizeof(lv_color_t) == sizeof(uint16_t), "lv_color_t must be 16b wide");
+                encode_base64(buf, index, color_map[i].full);
+            }
+            buf[initial_offset + (size-1) * 3 + 1] = '\0';
+
+            event_occured("TFT_W", buf);
+            free(buf);
+        } else {
+            ESP_LOGE("tft_track_state", "buffer alloc failed!");
+        }
+    }
+
+    #endif
 }
 
 static void IRAM_ATTR lv_tick_task(void *param) {
@@ -150,10 +198,10 @@ static void guiTask(void *pvParameter) {
     ESP_ERROR_CHECK(esp_timer_create(&lvgl_tick_timer_args, &periodic_timer));
     ESP_ERROR_CHECK(esp_timer_start_periodic(periodic_timer, LVGL_UPDATE_PERIOD_MS * 1000));
 
-    screen = lv_disp_get_scr_act(NULL);
+    screen = lv_scr_act();
     lv_style_init(&style_screen);
     lv_style_set_bg_color(&style_screen, lv_color_black());
-    lv_obj_add_style(lv_scr_act(), &style_screen, LV_STATE_DEFAULT);
+    lv_obj_add_style(screen, &style_screen, LV_STATE_DEFAULT);
 
     while (1) {
         /* Delay 1 tick (assumes FreeRTOS tick is 10ms */
@@ -169,14 +217,6 @@ static void guiTask(void *pvParameter) {
     vTaskDelete(NULL);
 }
 
-static void tick_timer_task(void* arg) {
-    while (1)
-    {
-        lv_task_handler();
-        vTaskDelay(pdMS_TO_TICKS(10));
-    }
-}
-
 void init_tft() {
     ESP_LOGI(TAG, "Initializing TFT...");
 
@@ -184,7 +224,5 @@ void init_tft() {
     initialize_display();
     xTaskCreatePinnedToCore(guiTask, "gui", 4096*2, NULL, 5, NULL, 1);
 
-    // xTaskCreatePinnedToCore(tick_timer_task, "tick_lvgl", 4096, NULL, 5, NULL, 1);
-
     ESP_LOGI(TAG, "TFT initialized!");
 }