Prepared page handling. Added EPD frame selection.

main/PagePrinter.cpp

@@ -22,6 +22,6 @@ void PagePrinter::print(Page* page)
     EPD_setFont(font, NULL);
     text_wrap = 1;
     EPD_print(page->text, 0, 0);
-    EPD_UpdateScreen();
+    //EPD_UpdateScreen();
 
 }

main/TextReader.cpp

@@ -1,3 +1,4 @@
+#include <string.h>
 #include "TextReader.h"
 
 #include "esp_log.h"
@@ -15,6 +16,14 @@ void TextReader::close()
 
 size_t TextReader::read(long pos, char* text, size_t len)
 {
+    memset(text, 0, len);
+    if (pos < 0) {
+        len += pos;
+        pos = 0;
+    }
+    if (len <= 0) {
+        return 0;
+    }
     if (this->f == NULL) {
         ESP_LOGE(TAG, "File not opened.");
         sprintf(text, "File could not be opened.");

main/Typesetter.cpp

@@ -1,10 +1,34 @@
+#include <string.h>
 #include "Typesetter.h"
 
 Typesetter::Typesetter()
 {}
 
-void Typesetter::preparePage(Page* page, char* text, size_t len)
+Page* Typesetter::preparePage(char* text, size_t len)
 {
-    page->text = text;
+    Page* page = new Page;
+    page->text = new char[len+1];
+    memcpy(page->text, text, len);
+    page->text[len] = 0;
     page->len = len;
+    return page;
+}
+
+Page* Typesetter::preparePreviousPage(char* text, size_t len)
+{
+    Page* page = new Page;
+    page->text = new char[len+1];
+    memcpy(page->text, text, len);
+    page->text[len] = 0;
+    page->len = len;
+    return page;
+}
+
+void Typesetter::destroyPage(Page* page)
+{
+    if (page == NULL) {
+        return;
+    }
+    delete page->text;
+    delete page;
 }

main/Typesetter.h

@@ -6,8 +6,7 @@ class Typesetter
 public:
     Typesetter();
 
-    void preparePage(Page* page, char* text, size_t len);
-
-//private:
-
+    Page* preparePage(char* text, size_t len);
+    Page* preparePreviousPage(char* text, size_t len);
+    void destroyPage(Page* page);
 };

main/config.h

@@ -1,2 +1,4 @@
 
 #define APP_VERSION "0.1"
+
+#define DISPLAY_SLEEP_TIMEOUT 1000

main/display.c

@@ -12,10 +12,12 @@
 
 void display_init()
 {
+    // drawing buffer
 	disp_buffer = (uint8_t*)pvPortMallocCaps(EPD_DISPLAY_WIDTH * (EPD_DISPLAY_HEIGHT/8), MALLOC_CAP_DMA);
 	assert(disp_buffer);
 	drawBuff = disp_buffer;
 
+    // gray-scale drawing buffer
 	gs_disp_buffer = (uint8_t*)pvPortMallocCaps(EPD_DISPLAY_WIDTH * EPD_DISPLAY_HEIGHT, MALLOC_CAP_DMA);
 	assert(gs_disp_buffer);
 	gs_drawBuff = gs_disp_buffer;
@@ -67,8 +69,6 @@ void display_connect()
 
     printf("SPI: attached display device, speed=%u\r\n", spi_lobo_get_speed(disp_spi));
 	printf("SPI: bus uses native pins: %s\r\n", spi_lobo_uses_native_pins(disp_spi) ? "true" : "false");
-
-    //EPD_PowerOn();
 }
 
 void display_splash_screen()
@@ -100,3 +100,14 @@ void display_update()
 {
     EPD_UpdateScreen();
 }
+
+extern void EPD_wake();
+void display_wake()
+{
+    EPD_wake();
+}
+
+void display_sleep()
+{
+    EPD_PowerOff();
+}

main/display.h

@@ -5,4 +5,7 @@ void display_splash_screen();
 
 void display_clear();
 void display_refresh();
-void display_update();
+void display_update();
+
+void display_wake();
+void display_sleep();

main/main.cpp

@@ -59,22 +59,34 @@ extern "C" void app_main()
     PagePrinter pagePrinter;
     TextStorage textStorage;
     TextReader* textReader = textStorage.open("/sdcard/book.txt");
-    Page page;
+    Page* pageLast = NULL;
+    Page* pageCurrent = NULL;
 
     long bookmark = 0;
+    //bool displaySleeping = false;
 
     while (1) {
 		char text[1024];
         if (textReader != NULL) {
-            size_t read = textReader->read(bookmark, text, sizeof(text));
+            if (pageCurrent == NULL) {
+                size_t read = textReader->read(bookmark, text, sizeof(text));
+                pageCurrent = typesetter.preparePage(text, sizeof(text));
+            }
+            if (pageLast == NULL) {
+                size_t read = textReader->read(bookmark - sizeof(text), text, sizeof(text));
+                pageLast = typesetter.preparePreviousPage(text, sizeof(text));
+            }
         } else {
+            typesetter.destroyPage(pageCurrent);
             strcpy(text, "File could not be opened.");
+            pageCurrent = typesetter.preparePage(text, sizeof(text));
         }
-        typesetter.preparePage(&page, text, sizeof(text));
+
         display_clear();
-        pagePrinter.print(&page);
+        pagePrinter.print(pageCurrent);
         display_update();
 
+        //time_t idleStart = clock();
         while (1) {
             sleep(10);
             if (buttons_pressed_ok()) {
@@ -84,15 +96,39 @@ extern "C" void app_main()
             }
             if (buttons_pressed_plus()) {
                 ESP_LOGI(TAG, "Turn page PLUS.");
-                bookmark += sizeof(text);
+                if (pageCurrent != NULL) {
+                    bookmark += pageCurrent->len;
+                    typesetter.destroyPage(pageLast);
+                    pageLast = pageCurrent;
+                    pageCurrent = NULL;
+                } else {
+                    ESP_LOGW(TAG, "No current page.");
+                }
                 break;
             }
             if (buttons_pressed_minus()) {
                 ESP_LOGI(TAG, "Turn page MINUS.");
-                bookmark -= sizeof(text);
+                if (pageLast != NULL) {
+                    bookmark -= pageLast->len;
+                    typesetter.destroyPage(pageCurrent);
+                    pageCurrent = pageLast;
+                    pageLast = NULL;
+                } else {
+                    ESP_LOGW(TAG, "No last page.");
+                }
                 break;
             }
+            /*if (!displaySleeping && (clock() - idleStart > DISPLAY_SLEEP_TIMEOUT)) {
+                displaySleeping = true;
+                ESP_LOGI(TAG, "Display going to sleep after %d ms.", DISPLAY_SLEEP_TIMEOUT);
+                display_sleep();
+            }*/
         }
+        /*if (displaySleeping) {
+            displaySleeping = false;
+            ESP_LOGI(TAG, "Display waking up.");
+            display_wake();
+        }*/
     }
 
 }