Cut release 0.7.0

As discussed in
https://github.com/daveallie/crosspoint-reader/pull/38#issuecomment-3665142427,
#38

lib/EpdFont/scripts/fontconvert.py

@@ -176,7 +176,7 @@ for i_start, i_end in intervals:
                 px = 0
 
         if is2Bit:
-            # 0 = white, 15 black, 8+ dark grey, 7- light grey
+            # 0-3 white, 4-7 light grey, 8-11 dark grey, 12-15 black
             # Downsample to 2-bit bitmap
             pixels2b = []
             px = 0
@@ -187,11 +187,11 @@ for i_start, i_end in intervals:
                     bm = pixels4g[y * pitch + (x // 2)]
                     bm = (bm >> ((x % 2) * 4)) & 0xF
 
-                    if bm == 15:
+                    if bm >= 12:
                         px += 3
                     elif bm >= 8:
                         px += 2
-                    elif bm > 0:
+                    elif bm >= 4:
                         px += 1
 
                     if (y * bitmap.width + x) % 4 == 3:
@@ -211,7 +211,7 @@ for i_start, i_end in intervals:
             #     print(line)
             # print('')
         else:
-            # Downsample to 1-bit bitmap - treat any non-zero as black
+            # Downsample to 1-bit bitmap - treat any 2+ as black
             pixelsbw = []
             px = 0
             pitch = (bitmap.width // 2) + (bitmap.width % 2)
@@ -219,7 +219,7 @@ for i_start, i_end in intervals:
                 for x in range(bitmap.width):
                     px = px << 1
                     bm = pixels4g[y * pitch + (x // 2)]
-                    px += 1 if ((x & 1) == 0 and bm & 0xF > 0) or ((x & 1) == 1 and bm & 0xF0 > 0) else 0
+                    px += 1 if ((x & 1) == 0 and bm & 0xE > 0) or ((x & 1) == 1 and bm & 0xE0 > 0) else 0
 
                     if (y * bitmap.width + x) % 8 == 7:
                         pixelsbw.append(px)

lib/Epub/Epub.cpp

@@ -73,10 +73,8 @@ bool Epub::parseContentOpf(const std::string& contentOpfFilePath) {
     coverImageItem = opfParser.items.at(opfParser.coverItemId);
   }
 
-  if (opfParser.items.count("ncx")) {
-    tocNcxItem = opfParser.items.at("ncx");
-  } else if (opfParser.items.count("ncxtoc")) {
-    tocNcxItem = opfParser.items.at("ncxtoc");
+  if (!opfParser.tocNcxPath.empty()) {
+    tocNcxItem = opfParser.tocNcxPath;
   }
 
   for (auto& spineRef : opfParser.spineRefs) {
@@ -150,11 +148,54 @@ bool Epub::load() {
     return false;
   }
 
+  initializeSpineItemSizes();
   Serial.printf("[%lu] [EBP] Loaded ePub: %s\n", millis(), filepath.c_str());
 
   return true;
 }
 
+void Epub::initializeSpineItemSizes() {
+  setupCacheDir();
+
+  size_t spineItemsCount = getSpineItemsCount();
+  size_t cumSpineItemSize = 0;
+  if (SD.exists((getCachePath() + "/spine_size.bin").c_str())) {
+    File f = SD.open((getCachePath() + "/spine_size.bin").c_str());
+    uint8_t data[4];
+    for (size_t i = 0; i < spineItemsCount; i++) {
+      f.read(data, 4);
+      cumSpineItemSize = data[0] | (data[1] << 8) | (data[2] << 16) | (data[3] << 24);
+      cumulativeSpineItemSize.emplace_back(cumSpineItemSize);
+      // Serial.printf("[%lu] [EBP] Loading item %d size %u to %u %u\n", millis(),
+      //     i, cumSpineItemSize, data[1], data[0]);
+    }
+    f.close();
+  } else {
+    File f = SD.open((getCachePath() + "/spine_size.bin").c_str(), FILE_WRITE);
+    uint8_t data[4];
+    // determine size of spine items
+    for (size_t i = 0; i < spineItemsCount; i++) {
+      std::string spineItem = getSpineItem(i);
+      size_t s = 0;
+      getItemSize(spineItem, &s);
+      cumSpineItemSize += s;
+      cumulativeSpineItemSize.emplace_back(cumSpineItemSize);
+
+      // and persist to cache
+      data[0] = cumSpineItemSize & 0xFF;
+      data[1] = (cumSpineItemSize >> 8) & 0xFF;
+      data[2] = (cumSpineItemSize >> 16) & 0xFF;
+      data[3] = (cumSpineItemSize >> 24) & 0xFF;
+      // Serial.printf("[%lu] [EBP] Persisting item %d size %u to %u %u\n", millis(),
+      //     i, cumSpineItemSize, data[1], data[0]);
+      f.write(data, 4);
+    }
+
+    f.close();
+  }
+  Serial.printf("[%lu] [EBP] Book size: %lu\n", millis(), cumSpineItemSize);
+}
+
 bool Epub::clearCache() const {
   if (!SD.exists(cachePath.c_str())) {
     Serial.printf("[%lu] [EPB] Cache does not exist, no action needed\n", millis());
@@ -257,6 +298,8 @@ bool Epub::getItemSize(const std::string& itemHref, size_t* size) const {
 
 int Epub::getSpineItemsCount() const { return spine.size(); }
 
+size_t Epub::getCumulativeSpineItemSize(const int spineIndex) const { return cumulativeSpineItemSize.at(spineIndex); }
+
 std::string& Epub::getSpineItem(const int spineIndex) {
   if (spineIndex < 0 || spineIndex >= spine.size()) {
     Serial.printf("[%lu] [EBP] getSpineItem index:%d is out of range\n", millis(), spineIndex);
@@ -304,3 +347,14 @@ int Epub::getTocIndexForSpineIndex(const int spineIndex) const {
   Serial.printf("[%lu] [EBP] TOC item not found\n", millis());
   return -1;
 }
+
+size_t Epub::getBookSize() const { return getCumulativeSpineItemSize(getSpineItemsCount() - 1); }
+
+// Calculate progress in book
+uint8_t Epub::calculateProgress(const int currentSpineIndex, const float currentSpineRead) {
+  size_t prevChapterSize = (currentSpineIndex >= 1) ? getCumulativeSpineItemSize(currentSpineIndex - 1) : 0;
+  size_t curChapterSize = getCumulativeSpineItemSize(currentSpineIndex) - prevChapterSize;
+  size_t bookSize = getBookSize();
+  size_t sectionProgSize = currentSpineRead * curChapterSize;
+  return round(static_cast<float>(prevChapterSize + sectionProgSize) / bookSize * 100.0);
+}

lib/Epub/Epub.h

@@ -20,6 +20,8 @@ class Epub {
   std::string filepath;
   // the spine of the EPUB file
   std::vector<std::pair<std::string, std::string>> spine;
+  // the file size of the spine items (proxy to book progress)
+  std::vector<size_t> cumulativeSpineItemSize;
   // the toc of the EPUB file
   std::vector<EpubTocEntry> toc;
   // the base path for items in the EPUB file
@@ -30,6 +32,7 @@ class Epub {
   bool findContentOpfFile(std::string* contentOpfFile) const;
   bool parseContentOpf(const std::string& contentOpfFilePath);
   bool parseTocNcxFile();
+  void initializeSpineItemSizes();
 
  public:
   explicit Epub(std::string filepath, const std::string& cacheDir) : filepath(std::move(filepath)) {
@@ -51,8 +54,12 @@ class Epub {
   bool getItemSize(const std::string& itemHref, size_t* size) const;
   std::string& getSpineItem(int spineIndex);
   int getSpineItemsCount() const;
-  EpubTocEntry& getTocItem(int tocTndex);
+  size_t getCumulativeSpineItemSize(const int spineIndex) const;
+  EpubTocEntry& getTocItem(int tocIndex);
   int getTocItemsCount() const;
   int getSpineIndexForTocIndex(int tocIndex) const;
   int getTocIndexForSpineIndex(int spineIndex) const;
+
+  size_t getBookSize() const;
+  uint8_t calculateProgress(const int currentSpineIndex, const float currentSpineRead);
 };

lib/Epub/Epub/Page.cpp

@@ -3,7 +3,9 @@
 #include <HardwareSerial.h>
 #include <Serialization.h>
 
+namespace {
 constexpr uint8_t PAGE_FILE_VERSION = 3;
+}
 
 void PageLine::render(GfxRenderer& renderer, const int fontId) { block->render(renderer, fontId, xPos, yPos); }
 

lib/Epub/Epub/Section.cpp

@@ -9,7 +9,9 @@
 #include "Page.h"
 #include "parsers/ChapterHtmlSlimParser.h"
 
+namespace {
 constexpr uint8_t SECTION_FILE_VERSION = 5;
+}
 
 void Section::onPageComplete(std::unique_ptr<Page> page) {
   const auto filePath = cachePath + "/page_" + std::to_string(pageCount) + ".bin";

lib/Epub/Epub/parsers/ContentOpfParser.cpp

@@ -3,6 +3,10 @@
 #include <HardwareSerial.h>
 #include <ZipFile.h>
 
+namespace {
+constexpr const char MEDIA_TYPE_NCX[] = "application/x-dtbncx+xml";
+}
+
 bool ContentOpfParser::setup() {
   parser = XML_ParserCreate(nullptr);
   if (!parser) {
@@ -111,16 +115,28 @@ void XMLCALL ContentOpfParser::startElement(void* userData, const XML_Char* name
   if (self->state == IN_MANIFEST && (strcmp(name, "item") == 0 || strcmp(name, "opf:item") == 0)) {
     std::string itemId;
     std::string href;
+    std::string mediaType;
 
     for (int i = 0; atts[i]; i += 2) {
       if (strcmp(atts[i], "id") == 0) {
         itemId = atts[i + 1];
       } else if (strcmp(atts[i], "href") == 0) {
         href = self->baseContentPath + atts[i + 1];
+      } else if (strcmp(atts[i], "media-type") == 0) {
+        mediaType = atts[i + 1];
       }
     }
 
     self->items[itemId] = href;
+
+    if (mediaType == MEDIA_TYPE_NCX) {
+      if (self->tocNcxPath.empty()) {
+        self->tocNcxPath = href;
+      } else {
+        Serial.printf("[%lu] [COF] Warning: Multiple NCX files found in manifest. Ignoring duplicate: %s\n", millis(),
+                      href.c_str());
+      }
+    }
     return;
   }
 

lib/GfxRenderer/GfxRenderer.cpp

@@ -132,13 +132,19 @@ void GfxRenderer::displayBuffer(const EInkDisplay::RefreshMode refreshMode) cons
   einkDisplay.displayBuffer(refreshMode);
 }
 
-// TODO: Support partial window update
-// void GfxRenderer::flushArea(const int x, const int y, const int width, const int height) const {
-//   const int rotatedX = y;
-//   const int rotatedY = EInkDisplay::DISPLAY_HEIGHT - 1 - x;
-//
-//   einkDisplay.displayBuffer(EInkDisplay::FAST_REFRESH, rotatedX, rotatedY, height, width);
-// }
+void GfxRenderer::displayWindow(const int x, const int y, const int width, const int height) const {
+  // Rotate coordinates from portrait (480x800) to landscape (800x480)
+  // Rotation: 90 degrees clockwise
+  // Portrait coordinates: (x, y) with dimensions (width, height)
+  // Landscape coordinates: (rotatedX, rotatedY) with dimensions (rotatedWidth, rotatedHeight)
+
+  const int rotatedX = y;
+  const int rotatedY = EInkDisplay::DISPLAY_HEIGHT - 1 - x - width + 1;
+  const int rotatedWidth = height;
+  const int rotatedHeight = width;
+
+  einkDisplay.displayWindow(rotatedX, rotatedY, rotatedWidth, rotatedHeight);
+}
 
 // Note: Internal driver treats screen in command orientation, this library treats in portrait orientation
 int GfxRenderer::getScreenWidth() { return EInkDisplay::DISPLAY_HEIGHT; }
@@ -164,7 +170,7 @@ int GfxRenderer::getLineHeight(const int fontId) const {
 
 uint8_t* GfxRenderer::getFrameBuffer() const { return einkDisplay.getFrameBuffer(); }
 
-void GfxRenderer::swapBuffers() const { einkDisplay.swapBuffers(); }
+size_t GfxRenderer::getBufferSize() { return EInkDisplay::BUFFER_SIZE; }
 
 void GfxRenderer::grayscaleRevert() const { einkDisplay.grayscaleRevert(); }
 
@@ -174,6 +180,90 @@ void GfxRenderer::copyGrayscaleMsbBuffers() const { einkDisplay.copyGrayscaleMsb
 
 void GfxRenderer::displayGrayBuffer() const { einkDisplay.displayGrayBuffer(); }
 
+void GfxRenderer::freeBwBufferChunks() {
+  for (auto& bwBufferChunk : bwBufferChunks) {
+    if (bwBufferChunk) {
+      free(bwBufferChunk);
+      bwBufferChunk = nullptr;
+    }
+  }
+}
+
+/**
+ * This should be called before grayscale buffers are populated.
+ * A `restoreBwBuffer` call should always follow the grayscale render if this method was called.
+ * Uses chunked allocation to avoid needing 48KB of contiguous memory.
+ */
+void GfxRenderer::storeBwBuffer() {
+  const uint8_t* frameBuffer = einkDisplay.getFrameBuffer();
+
+  // Allocate and copy each chunk
+  for (size_t i = 0; i < BW_BUFFER_NUM_CHUNKS; i++) {
+    // Check if any chunks are already allocated
+    if (bwBufferChunks[i]) {
+      Serial.printf("[%lu] [GFX] !! BW buffer chunk %zu already stored - this is likely a bug, freeing chunk\n",
+                    millis(), i);
+      free(bwBufferChunks[i]);
+      bwBufferChunks[i] = nullptr;
+    }
+
+    const size_t offset = i * BW_BUFFER_CHUNK_SIZE;
+    bwBufferChunks[i] = static_cast<uint8_t*>(malloc(BW_BUFFER_CHUNK_SIZE));
+
+    if (!bwBufferChunks[i]) {
+      Serial.printf("[%lu] [GFX] !! Failed to allocate BW buffer chunk %zu (%zu bytes)\n", millis(), i,
+                    BW_BUFFER_CHUNK_SIZE);
+      // Free previously allocated chunks
+      freeBwBufferChunks();
+      return;
+    }
+
+    memcpy(bwBufferChunks[i], frameBuffer + offset, BW_BUFFER_CHUNK_SIZE);
+  }
+
+  Serial.printf("[%lu] [GFX] Stored BW buffer in %zu chunks (%zu bytes each)\n", millis(), BW_BUFFER_NUM_CHUNKS,
+                BW_BUFFER_CHUNK_SIZE);
+}
+
+/**
+ * This can only be called if `storeBwBuffer` was called prior to the grayscale render.
+ * It should be called to restore the BW buffer state after grayscale rendering is complete.
+ * Uses chunked restoration to match chunked storage.
+ */
+void GfxRenderer::restoreBwBuffer() {
+  // Check if any all chunks are allocated
+  bool missingChunks = false;
+  for (const auto& bwBufferChunk : bwBufferChunks) {
+    if (!bwBufferChunk) {
+      missingChunks = true;
+      break;
+    }
+  }
+
+  if (missingChunks) {
+    freeBwBufferChunks();
+    return;
+  }
+
+  uint8_t* frameBuffer = einkDisplay.getFrameBuffer();
+  for (size_t i = 0; i < BW_BUFFER_NUM_CHUNKS; i++) {
+    // Check if chunk is missing
+    if (!bwBufferChunks[i]) {
+      Serial.printf("[%lu] [GFX] !! BW buffer chunks not stored - this is likely a bug\n", millis());
+      freeBwBufferChunks();
+      return;
+    }
+
+    const size_t offset = i * BW_BUFFER_CHUNK_SIZE;
+    memcpy(frameBuffer + offset, bwBufferChunks[i], BW_BUFFER_CHUNK_SIZE);
+  }
+
+  einkDisplay.cleanupGrayscaleBuffers(frameBuffer);
+
+  freeBwBufferChunks();
+  Serial.printf("[%lu] [GFX] Restored and freed BW buffer chunks\n", millis());
+}
+
 void GfxRenderer::renderChar(const EpdFontFamily& fontFamily, const uint32_t cp, int* x, const int* y,
                              const bool pixelState, const EpdFontStyle style) const {
   const EpdGlyph* glyph = fontFamily.getGlyph(cp, style);

lib/GfxRenderer/GfxRenderer.h

@@ -10,11 +10,18 @@ class GfxRenderer {
   enum RenderMode { BW, GRAYSCALE_LSB, GRAYSCALE_MSB };
 
  private:
+  static constexpr size_t BW_BUFFER_CHUNK_SIZE = 8000;  // 8KB chunks to allow for non-contiguous memory
+  static constexpr size_t BW_BUFFER_NUM_CHUNKS = EInkDisplay::BUFFER_SIZE / BW_BUFFER_CHUNK_SIZE;
+  static_assert(BW_BUFFER_CHUNK_SIZE * BW_BUFFER_NUM_CHUNKS == EInkDisplay::BUFFER_SIZE,
+                "BW buffer chunking does not line up with display buffer size");
+
   EInkDisplay& einkDisplay;
   RenderMode renderMode;
+  uint8_t* bwBufferChunks[BW_BUFFER_NUM_CHUNKS] = {nullptr};
   std::map<int, EpdFontFamily> fontMap;
   void renderChar(const EpdFontFamily& fontFamily, uint32_t cp, int* x, const int* y, bool pixelState,
                   EpdFontStyle style) const;
+  void freeBwBufferChunks();
 
  public:
   explicit GfxRenderer(EInkDisplay& einkDisplay) : einkDisplay(einkDisplay), renderMode(BW) {}
@@ -27,6 +34,8 @@ class GfxRenderer {
   static int getScreenWidth();
   static int getScreenHeight();
   void displayBuffer(EInkDisplay::RefreshMode refreshMode = EInkDisplay::FAST_REFRESH) const;
+  // EXPERIMENTAL: Windowed update - display only a rectangular region (portrait coordinates)
+  void displayWindow(int x, int y, int width, int height) const;
   void invertScreen() const;
   void clearScreen(uint8_t color = 0xFF) const;
 
@@ -49,9 +58,11 @@ class GfxRenderer {
   void copyGrayscaleLsbBuffers() const;
   void copyGrayscaleMsbBuffers() const;
   void displayGrayBuffer() const;
+  void storeBwBuffer();
+  void restoreBwBuffer();
 
   // Low level functions
   uint8_t* getFrameBuffer() const;
-  void swapBuffers() const;
+  static size_t getBufferSize();
   void grayscaleRevert() const;
 };

platformio.ini

@@ -1,5 +1,5 @@
 [platformio]
-crosspoint_version = 0.6.0
+crosspoint_version = 0.7.0
 default_envs = default
 
 [base]
@@ -20,6 +20,7 @@ build_flags =
   -DARDUINO_USB_MODE=1
   -DARDUINO_USB_CDC_ON_BOOT=1
   -DMINIZ_NO_ZLIB_COMPATIBLE_NAMES=1
+  -DEINK_DISPLAY_SINGLE_BUFFER_MODE=1
 # https://libexpat.github.io/doc/api/latest/#XML_GE
   -DXML_GE=0
   -DXML_CONTEXT_BYTES=1024

src/CrossPointSettings.cpp

@@ -10,9 +10,11 @@
 // Initialize the static instance
 CrossPointSettings CrossPointSettings::instance;
 
+namespace {
 constexpr uint8_t SETTINGS_FILE_VERSION = 1;
 constexpr uint8_t SETTINGS_COUNT = 2;
 constexpr char SETTINGS_FILE[] = "/sd/.crosspoint/settings.bin";
+}  // namespace
 
 bool CrossPointSettings::saveToFile() const {
   // Make sure the directory exists

src/CrossPointState.cpp

@@ -6,8 +6,12 @@
 
 #include <fstream>
 
+namespace {
 constexpr uint8_t STATE_FILE_VERSION = 1;
 constexpr char STATE_FILE[] = "/sd/.crosspoint/state.bin";
+}  // namespace
+
+CrossPointState CrossPointState::instance;
 
 bool CrossPointState::saveToFile() const {
   std::ofstream outputFile(STATE_FILE);