From c539322a3661095b2b7da653520f4b64e8ffbccb Mon Sep 17 00:00:00 2001
From: martinberlin <martin@luckycloud.de>
Date: Fri, 11 Jun 2021 12:39:00 +0200
Subject: [PATCH] Using epdiy_set_px_cb *buf and returning *color_map in flush
 method to update only the part that is updated. Still buggy but working
 version

---
 lvgl_tft/epdiy_epaper_v2.cpp | 154 +++++++++++++++++++++++++++++++++++
 1 file changed, 154 insertions(+)
 create mode 100644 lvgl_tft/epdiy_epaper_v2.cpp

diff --git a/lvgl_tft/epdiy_epaper_v2.cpp b/lvgl_tft/epdiy_epaper_v2.cpp
new file mode 100644
index 0000000..2314b1e
--- /dev/null
+++ b/lvgl_tft/epdiy_epaper_v2.cpp
@@ -0,0 +1,154 @@
+#include "esp_log.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+
+#include "epdiy_epaper.h"
+
+#include "epd_driver.h"
+#include "epd_highlevel.h"
+// Usable size
+#include <malloc.h>
+/*********************
+ *      DEFINES
+ *********************/
+#define TAG "EPDIY"
+EpdiyHighlevelState hl;
+uint16_t flushcalls = 0;
+uint8_t * framebuffer;
+
+uint8_t temperature = 25;
+
+/* Display initialization routine */
+void epdiy_init(void)
+{
+    epd_init(EPD_OPTIONS_DEFAULT);
+    hl = epd_hl_init(EPD_BUILTIN_WAVEFORM);
+    framebuffer = epd_hl_get_framebuffer(&hl);    
+    epd_poweron();
+    //Clear all always in init?
+    epd_fullclear(&hl, temperature);
+}
+
+uint16_t xo = 0;
+uint16_t yo = 0;
+uint16_t rx = 0;
+uint16_t ry = 0;
+uint16_t rw = 0;
+uint16_t rh = 0;
+
+void buf_copy_to_framebuffer(EpdRect image_area, const uint8_t *image_data) {
+
+  assert(framebuffer != NULL);
+
+  for (uint32_t i = 0; i < image_area.width * image_area.height; i++) {
+
+    uint32_t value_index = i;
+    // for images of uneven width consume an additional nibble per row.
+    if (image_area.width % 2) {
+      value_index += i / image_area.width;
+    }
+    // Get out if we get the end of the buffer  (image_data[value_index / 2]== '\0')  111684
+    if (value_index / 2 > 111600) {
+        printf("FOUND END incr:%d img[idx]:%d Aw:%d Ah:%d\n", i, 
+        value_index / 2,image_area.width,image_area.height);
+        break;
+    } 
+    
+    uint8_t val = (value_index % 2) ? (image_data[value_index / 2] & 0xF0) >> 4
+                                    : image_data[value_index / 2] & 0x0F;
+
+    int xx = image_area.x + i % image_area.width;
+    if (xx < 0 || xx >= EPD_WIDTH) {
+      continue;
+    }
+    int yy = image_area.y + i / image_area.width;
+    if (yy < 0 || yy >= EPD_HEIGHT) {
+      continue;
+    }
+    uint8_t *buf_ptr = &framebuffer[yy * EPD_WIDTH / 2 + xx / 2];
+    if (xx % 2) {
+      *buf_ptr = (*buf_ptr & 0x0F) | (val << 4);
+    } else {
+      *buf_ptr = (*buf_ptr & 0xF0) | val;
+    }
+  }
+}
+
+/* Required by LVGL */
+void epdiy_flush(lv_disp_drv_t *drv, const lv_area_t *area, lv_color_t *color_map)
+{
+    ++flushcalls;
+    xo = area->x1;
+    yo = area->y1;
+    uint16_t w = lv_area_get_width(area);
+    uint16_t h = lv_area_get_height(area);
+
+    EpdRect update_area = {
+        .x = xo,
+        .y = yo,
+        .width = w,
+        .height = h,
+    };
+
+    uint8_t* buf = (uint8_t *) color_map;
+    // Buffer debug
+    /* 
+    for (int index=0; index<400; index++) {
+        printf("%x ", buf[index]);
+    } */
+
+    // Does not work for full screen update yet (Should check large of bug)
+    if (flushcalls>0){
+      buf_copy_to_framebuffer(update_area, buf);
+    }
+
+    epd_hl_update_area(&hl, MODE_GC16, temperature, update_area); //update_area
+
+    printf("epdiy_flush %d x:%d y:%d w:%d h:%d\n", flushcalls,xo,yo,w,h);
+    //printf("epdiy_flush Rounder() x:%d y:%d w:%d h:%d\n",rx,ry,rw,rh);
+    /* Inform the graphics library that you are ready with the flushing */
+    lv_disp_flush_ready(drv);
+}
+
+/* 
+ * Called for each pixel. Designed with the idea to fill the buffer directly, not to set each pixel, see:
+ * https://forum.lvgl.io/t/lvgl-port-to-be-used-with-epaper-displays/5630/3
+*/
+void epdiy_set_px_cb(lv_disp_drv_t * disp_drv, uint8_t* buf,
+    lv_coord_t buf_w, lv_coord_t x, lv_coord_t y,
+    lv_color_t color, lv_opa_t opa)
+{
+    // Test using RGB232
+    int16_t epd_color = 255;
+    if ((int16_t)color.full<250) {
+        epd_color = (int16_t)color.full/3;
+    }
+
+    //Instead of using epd_draw_pixel: Set pixel directly in buffer
+    uint16_t idx = (int16_t)y * buf_w / 2 + (int16_t)x / 2;
+    if (x % 2) {
+        buf[idx] = (buf[idx] & 0x0F) | (epd_color & 0xF0);
+    } else {
+        buf[idx] = (buf[idx] & 0xF0) | (epd_color >> 4);
+    }
+
+    // Directly in framebuffer for epaper
+    /* uint8_t *buf_ptr = &framebuffer[(int16_t)y * buf_w / 2 + (int16_t)x / 2];
+    if (x % 2) {
+        *buf_ptr = (*buf_ptr & 0x0F) | (epd_color & 0xF0);
+    } else {
+        *buf_ptr = (*buf_ptr & 0xF0) | (epd_color >> 4);
+    } */
+}
+
+void epdiy_rounder_cb(lv_disp_drv_t *disp_drv, lv_area_t *area) {
+    // Print coordinates to understand what rounder is
+    /* rx = (int16_t)area->x1;
+    ry = (int16_t)area->y1;
+    rw = (int16_t)lv_area_get_width(area);
+    rh = (int16_t)lv_area_get_height(area);
+    printf("R x:%d y:%d y1:%d w:%d h:%d\n",rx,ry,area->y1,rw,rh); */
+
+    // Force y to be 0: Make some things better, screws other things
+    //area->y1 = 0;
+}
\ No newline at end of file