Feature/cover crop mode (#225)

Added a setting to select `fit` or `crop` for cover image on sleep
screen.

Might add a `expand` feature in the future that does not crop but rather
fills the blank space with a mirror of the image.

---------

Co-authored-by: Dave Allie <dave@daveallie.com>

lib/GfxRenderer/Bitmap.cpp

@@ -250,34 +250,29 @@ BmpReaderError Bitmap::parseHeaders() {
     delete[] errorNextRow;
     errorCurRow = new int16_t[width + 2]();  // +2 for boundary handling
     errorNextRow = new int16_t[width + 2]();
-    lastRowY = -1;
+    prevRowY = -1;
   }
 
   return BmpReaderError::Ok;
 }
 
 // packed 2bpp output, 0 = black, 1 = dark gray, 2 = light gray, 3 = white
-BmpReaderError Bitmap::readRow(uint8_t* data, uint8_t* rowBuffer, int rowY) const {
+BmpReaderError Bitmap::readNextRow(uint8_t* data, uint8_t* rowBuffer) const {
   // Note: rowBuffer should be pre-allocated by the caller to size 'rowBytes'
   if (file.read(rowBuffer, rowBytes) != rowBytes) return BmpReaderError::ShortReadRow;
 
   // Handle Floyd-Steinberg error buffer progression
   const bool useFS = USE_FLOYD_STEINBERG && errorCurRow && errorNextRow;
   if (useFS) {
-    // Check if we need to advance to next row (or reset if jumping)
+    if (prevRowY != -1) {
-    if (rowY != lastRowY + 1 && rowY != 0) {
-      // Non-sequential row access - reset error buffers
-      memset(errorCurRow, 0, (width + 2) * sizeof(int16_t));
-      memset(errorNextRow, 0, (width + 2) * sizeof(int16_t));
-    } else if (rowY > 0) {
       // Sequential access - swap buffers
       int16_t* temp = errorCurRow;
       errorCurRow = errorNextRow;
       errorNextRow = temp;
       memset(errorNextRow, 0, (width + 2) * sizeof(int16_t));
     }
-    lastRowY = rowY;
   }
+  prevRowY += 1;
 
   uint8_t* outPtr = data;
   uint8_t currentOutByte = 0;
@@ -292,7 +287,7 @@ BmpReaderError Bitmap::readRow(uint8_t* data, uint8_t* rowBuffer, int rowY) cons
       color = quantizeFloydSteinberg(lum, currentX, width, errorCurRow, errorNextRow, false);
     } else {
       // Simple quantization or noise dithering
-      color = quantize(lum, currentX, rowY);
+      color = quantize(lum, currentX, prevRowY);
     }
     currentOutByte |= (color << bitShift);
     if (bitShift == 0) {
@@ -365,7 +360,7 @@ BmpReaderError Bitmap::rewindToData() const {
   if (USE_FLOYD_STEINBERG && errorCurRow && errorNextRow) {
     memset(errorCurRow, 0, (width + 2) * sizeof(int16_t));
     memset(errorNextRow, 0, (width + 2) * sizeof(int16_t));
-    lastRowY = -1;
+    prevRowY = -1;
   }
 
   return BmpReaderError::Ok;

lib/GfxRenderer/Bitmap.h

@@ -31,7 +31,7 @@ class Bitmap {
   explicit Bitmap(FsFile& file) : file(file) {}
   ~Bitmap();
   BmpReaderError parseHeaders();
-  BmpReaderError readRow(uint8_t* data, uint8_t* rowBuffer, int rowY) const;
+  BmpReaderError readNextRow(uint8_t* data, uint8_t* rowBuffer) const;
   BmpReaderError rewindToData() const;
   int getWidth() const { return width; }
   int getHeight() const { return height; }
@@ -55,5 +55,5 @@ class Bitmap {
   // Floyd-Steinberg dithering state (mutable for const methods)
   mutable int16_t* errorCurRow = nullptr;
   mutable int16_t* errorNextRow = nullptr;
-  mutable int lastRowY = -1;  // Track row progression for error propagation
+  mutable int prevRowY = -1;  // Track row progression for error propagation
 };

lib/GfxRenderer/GfxRenderer.cpp

@@ -152,18 +152,24 @@ void GfxRenderer::drawImage(const uint8_t bitmap[], const int x, const int y, co
   einkDisplay.drawImage(bitmap, rotatedX, rotatedY, width, height);
 }
 
-void GfxRenderer::drawBitmap(const Bitmap& bitmap, const int x, const int y, const int maxWidth,
+void GfxRenderer::drawBitmap(const Bitmap& bitmap, const int x, const int y, const int maxWidth, const int maxHeight,
-                             const int maxHeight) const {
+                             const float cropX, const float cropY) const {
   float scale = 1.0f;
   bool isScaled = false;
-  if (maxWidth > 0 && bitmap.getWidth() > maxWidth) {
+  int cropPixX = std::floor(bitmap.getWidth() * cropX / 2.0f);
-    scale = static_cast<float>(maxWidth) / static_cast<float>(bitmap.getWidth());
+  int cropPixY = std::floor(bitmap.getHeight() * cropY / 2.0f);
+  Serial.printf("[%lu] [GFX] Cropping %dx%d by %dx%d pix, is %s\n", millis(), bitmap.getWidth(), bitmap.getHeight(),
+                cropPixX, cropPixY, bitmap.isTopDown() ? "top-down" : "bottom-up");
+
+  if (maxWidth > 0 && (1.0f - cropX) * bitmap.getWidth() > maxWidth) {
+    scale = static_cast<float>(maxWidth) / static_cast<float>((1.0f - cropX) * bitmap.getWidth());
     isScaled = true;
   }
-  if (maxHeight > 0 && bitmap.getHeight() > maxHeight) {
+  if (maxHeight > 0 && (1.0f - cropY) * bitmap.getHeight() > maxHeight) {
-    scale = std::min(scale, static_cast<float>(maxHeight) / static_cast<float>(bitmap.getHeight()));
+    scale = std::min(scale, static_cast<float>(maxHeight) / static_cast<float>((1.0f - cropY) * bitmap.getHeight()));
     isScaled = true;
   }
+  Serial.printf("[%lu] [GFX] Scaling by %f - %s\n", millis(), scale, isScaled ? "scaled" : "not scaled");
 
   // Calculate output row size (2 bits per pixel, packed into bytes)
   // IMPORTANT: Use int, not uint8_t, to avoid overflow for images > 1020 pixels wide
@@ -178,29 +184,36 @@ void GfxRenderer::drawBitmap(const Bitmap& bitmap, const int x, const int y, con
     return;
   }
 
-  for (int bmpY = 0; bmpY < bitmap.getHeight(); bmpY++) {
+  for (int bmpY = 0; bmpY < (bitmap.getHeight() - cropPixY); bmpY++) {
     // The BMP's (0, 0) is the bottom-left corner (if the height is positive, top-left if negative).
     // Screen's (0, 0) is the top-left corner.
-    int screenY = y + (bitmap.isTopDown() ? bmpY : bitmap.getHeight() - 1 - bmpY);
+    int screenY = -cropPixY + (bitmap.isTopDown() ? bmpY : bitmap.getHeight() - 1 - bmpY);
     if (isScaled) {
       screenY = std::floor(screenY * scale);
     }
+    screenY += y;  // the offset should not be scaled
     if (screenY >= getScreenHeight()) {
       break;
     }
 
-    if (bitmap.readRow(outputRow, rowBytes, bmpY) != BmpReaderError::Ok) {
+    if (bitmap.readNextRow(outputRow, rowBytes) != BmpReaderError::Ok) {
       Serial.printf("[%lu] [GFX] Failed to read row %d from bitmap\n", millis(), bmpY);
       free(outputRow);
       free(rowBytes);
       return;
     }
 
-    for (int bmpX = 0; bmpX < bitmap.getWidth(); bmpX++) {
+    if (bmpY < cropPixY) {
-      int screenX = x + bmpX;
+      // Skip the row if it's outside the crop area
+      continue;
+    }
+
+    for (int bmpX = cropPixX; bmpX < bitmap.getWidth() - cropPixX; bmpX++) {
+      int screenX = bmpX - cropPixX;
       if (isScaled) {
         screenX = std::floor(screenX * scale);
       }
+      screenX += x;  // the offset should not be scaled
       if (screenX >= getScreenWidth()) {
         break;
       }

lib/GfxRenderer/GfxRenderer.h

@@ -66,7 +66,8 @@ class GfxRenderer {
   void drawRect(int x, int y, int width, int height, bool state = true) const;
   void fillRect(int x, int y, int width, int height, bool state = true) const;
   void drawImage(const uint8_t bitmap[], int x, int y, int width, int height) const;
-  void drawBitmap(const Bitmap& bitmap, int x, int y, int maxWidth, int maxHeight) const;
+  void drawBitmap(const Bitmap& bitmap, int x, int y, int maxWidth, int maxHeight, float cropX = 0,
+                  float cropY = 0) const;
 
   // Text
   int getTextWidth(int fontId, const char* text, EpdFontFamily::Style style = EpdFontFamily::REGULAR) const;

lib/JpegToBmpConverter/JpegToBmpConverter.cpp

@@ -468,7 +468,9 @@ bool JpegToBmpConverter::jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut) {
     // Calculate scale to fit within target dimensions while maintaining aspect ratio
     const float scaleToFitWidth = static_cast<float>(TARGET_MAX_WIDTH) / imageInfo.m_width;
     const float scaleToFitHeight = static_cast<float>(TARGET_MAX_HEIGHT) / imageInfo.m_height;
-    const float scale = (scaleToFitWidth < scaleToFitHeight) ? scaleToFitWidth : scaleToFitHeight;
+    // We scale to the smaller dimension, so we can potentially crop later.
+    // TODO: ideally, we already crop here.
+    const float scale = (scaleToFitWidth > scaleToFitHeight) ? scaleToFitWidth : scaleToFitHeight;
 
     outWidth = static_cast<int>(imageInfo.m_width * scale);
     outHeight = static_cast<int>(imageInfo.m_height * scale);

src/CrossPointSettings.cpp

@@ -12,7 +12,7 @@ CrossPointSettings CrossPointSettings::instance;
 namespace {
 constexpr uint8_t SETTINGS_FILE_VERSION = 1;
 // Increment this when adding new persisted settings fields
-constexpr uint8_t SETTINGS_COUNT = 14;
+constexpr uint8_t SETTINGS_COUNT = 15;
 constexpr char SETTINGS_FILE[] = "/.crosspoint/settings.bin";
 }  // namespace
 
@@ -41,7 +41,7 @@ bool CrossPointSettings::saveToFile() const {
   serialization::writePod(outputFile, sleepTimeout);
   serialization::writePod(outputFile, refreshFrequency);
   serialization::writePod(outputFile, screenMargin);
-
+  serialization::writePod(outputFile, sleepScreenCoverMode);
   outputFile.close();
 
   Serial.printf("[%lu] [CPS] Settings saved to file\n", millis());
@@ -96,7 +96,8 @@ bool CrossPointSettings::loadFromFile() {
     if (++settingsRead >= fileSettingsCount) break;
     serialization::readPod(inputFile, screenMargin);
     if (++settingsRead >= fileSettingsCount) break;
-
+    serialization::readPod(inputFile, sleepScreenCoverMode);
+    if (++settingsRead >= fileSettingsCount) break;
   } while (false);
 
   inputFile.close();
@@ -212,4 +213,4 @@ int CrossPointSettings::getReaderFontId() const {
           return OPENDYSLEXIC_14_FONT_ID;
       }
   }
-}
+}

src/CrossPointSettings.h

@@ -17,6 +17,7 @@ class CrossPointSettings {
 
   // Should match with SettingsActivity text
   enum SLEEP_SCREEN_MODE { DARK = 0, LIGHT = 1, CUSTOM = 2, COVER = 3, BLANK = 4 };
+  enum SLEEP_SCREEN_COVER_MODE { FIT = 0, CROP = 1 };
 
   // Status bar display type enum
   enum STATUS_BAR_MODE { NONE = 0, NO_PROGRESS = 1, FULL = 2 };
@@ -53,6 +54,8 @@ class CrossPointSettings {
 
   // Sleep screen settings
   uint8_t sleepScreen = DARK;
+  // Sleep screen cover mode settings
+  uint8_t sleepScreenCoverMode = FIT;
   // Status bar settings
   uint8_t statusBar = FULL;
   // Text rendering settings

src/activities/boot_sleep/SleepActivity.cpp

@@ -146,20 +146,36 @@ void SleepActivity::renderBitmapSleepScreen(const Bitmap& bitmap) const {
   int x, y;
   const auto pageWidth = renderer.getScreenWidth();
   const auto pageHeight = renderer.getScreenHeight();
+  float cropX = 0, cropY = 0;
 
+  Serial.printf("[%lu] [SLP] bitmap %d x %d, screen %d x %d\n", millis(), bitmap.getWidth(), bitmap.getHeight(),
+                pageWidth, pageHeight);
   if (bitmap.getWidth() > pageWidth || bitmap.getHeight() > pageHeight) {
     // image will scale, make sure placement is right
-    const float ratio = static_cast<float>(bitmap.getWidth()) / static_cast<float>(bitmap.getHeight());
+    float ratio = static_cast<float>(bitmap.getWidth()) / static_cast<float>(bitmap.getHeight());
     const float screenRatio = static_cast<float>(pageWidth) / static_cast<float>(pageHeight);
 
+    Serial.printf("[%lu] [SLP] bitmap ratio: %f, screen ratio: %f\n", millis(), ratio, screenRatio);
     if (ratio > screenRatio) {
       // image wider than viewport ratio, scaled down image needs to be centered vertically
+      if (SETTINGS.sleepScreenCoverMode == CrossPointSettings::SLEEP_SCREEN_COVER_MODE::CROP) {
+        cropX = 1.0f - (screenRatio / ratio);
+        Serial.printf("[%lu] [SLP] Cropping bitmap x: %f\n", millis(), cropX);
+        ratio = (1.0f - cropX) * static_cast<float>(bitmap.getWidth()) / static_cast<float>(bitmap.getHeight());
+      }
       x = 0;
-      y = (pageHeight - pageWidth / ratio) / 2;
+      y = std::round((static_cast<float>(pageHeight) - static_cast<float>(pageWidth) / ratio) / 2);
+      Serial.printf("[%lu] [SLP] Centering with ratio %f to y=%d\n", millis(), ratio, y);
     } else {
       // image taller than viewport ratio, scaled down image needs to be centered horizontally
-      x = (pageWidth - pageHeight * ratio) / 2;
+      if (SETTINGS.sleepScreenCoverMode == CrossPointSettings::SLEEP_SCREEN_COVER_MODE::CROP) {
+        cropY = 1.0f - (ratio / screenRatio);
+        Serial.printf("[%lu] [SLP] Cropping bitmap y: %f\n", millis(), cropY);
+        ratio = static_cast<float>(bitmap.getWidth()) / ((1.0f - cropY) * static_cast<float>(bitmap.getHeight()));
+      }
+      x = std::round((pageWidth - pageHeight * ratio) / 2);
       y = 0;
+      Serial.printf("[%lu] [SLP] Centering with ratio %f to x=%d\n", millis(), ratio, x);
     }
   } else {
     // center the image
@@ -167,21 +183,22 @@ void SleepActivity::renderBitmapSleepScreen(const Bitmap& bitmap) const {
     y = (pageHeight - bitmap.getHeight()) / 2;
   }
 
+  Serial.printf("[%lu] [SLP] drawing to %d x %d\n", millis(), x, y);
   renderer.clearScreen();
-  renderer.drawBitmap(bitmap, x, y, pageWidth, pageHeight);
+  renderer.drawBitmap(bitmap, x, y, pageWidth, pageHeight, cropX, cropY);
   renderer.displayBuffer(EInkDisplay::HALF_REFRESH);
 
   if (bitmap.hasGreyscale()) {
     bitmap.rewindToData();
     renderer.clearScreen(0x00);
     renderer.setRenderMode(GfxRenderer::GRAYSCALE_LSB);
-    renderer.drawBitmap(bitmap, x, y, pageWidth, pageHeight);
+    renderer.drawBitmap(bitmap, x, y, pageWidth, pageHeight, cropX, cropY);
     renderer.copyGrayscaleLsbBuffers();
 
     bitmap.rewindToData();
     renderer.clearScreen(0x00);
     renderer.setRenderMode(GfxRenderer::GRAYSCALE_MSB);
-    renderer.drawBitmap(bitmap, x, y, pageWidth, pageHeight);
+    renderer.drawBitmap(bitmap, x, y, pageWidth, pageHeight, cropX, cropY);
     renderer.copyGrayscaleMsbBuffers();
 
     renderer.displayGrayBuffer();

src/activities/settings/SettingsActivity.cpp

@@ -10,10 +10,11 @@
 
 // Define the static settings list
 namespace {
-constexpr int settingsCount = 15;
+constexpr int settingsCount = 16;
 const SettingInfo settingsList[settingsCount] = {
     // Should match with SLEEP_SCREEN_MODE
     SettingInfo::Enum("Sleep Screen", &CrossPointSettings::sleepScreen, {"Dark", "Light", "Custom", "Cover", "None"}),
+    SettingInfo::Enum("Sleep Screen Cover Mode", &CrossPointSettings::sleepScreenCoverMode, {"Fit", "Crop"}),
     SettingInfo::Enum("Status Bar", &CrossPointSettings::statusBar, {"None", "No Progress", "Full"}),
     SettingInfo::Toggle("Extra Paragraph Spacing", &CrossPointSettings::extraParagraphSpacing),
     SettingInfo::Toggle("Short Power Button Click", &CrossPointSettings::shortPwrBtn),