Improved work on Font Handling, still not finished and also added a few testcases

src/drawing/font.rs

@@ -1,5 +1,108 @@
+//width must be multiple of 8
+//
+//chars are build in the bitmap like this example of a width 16, height 2 font:
+//12
+//34
+// first char is the first ascii letter you want
+#[allow(dead_code)]
+pub struct Font<'a> {
+    width: u8,
+    height: u8,
+    first_char: u8,
+    last_char: u8,
+    bitmap: &'a [u8],
+    widthmap: &'a [u8]
+}
+
+impl<'a> Font<'a> {
+    /// Panics if either Bitmap or Widthmap of the Font are to small for the amount and size of chars
+    pub fn new(width: u8, height: u8, first_char: u8, last_char: u8, bitmap: &'a [u8], widthmap: &'a [u8]) -> Font<'a> {
+        //Assertion so it shouldn't be able to panic later
+        let length_of_char = width as usize / 8 * height as usize;
+        let amount_of_chars = last_char as usize - first_char as usize + 1;
+        assert!(bitmap.len() >= amount_of_chars * length_of_char);
+        assert!(widthmap.len() >= amount_of_chars);
+
+        Font {width, height, first_char, last_char, bitmap, widthmap }
+
+    }
+
+    fn get_length_of_char(&self) -> usize {
+        self.width as usize / 8 * self.height as usize
+    }
+
+    fn get_char_pos(&self, input: char) -> usize {
+        (input as usize - self.first_char as usize)
+    }
+
+    /// Can panic, when end_pos > bitmap.len, should be caught in Font::new already
+    pub(crate) fn get_char(&'a self, input: char) -> &'a [u8] {
+        let start_pos = self.get_char_pos(input) * self.get_length_of_char();
+        let end_pos = start_pos + self.get_length_of_char();
+
+        &self.bitmap[start_pos .. end_pos]        
+    }
+
+    /// Can panic, when get_char_pos > widthmap.len(), should be caught in Font::new already
+    pub(crate) fn get_char_width(&self, input: char) -> u8 {
+        self.widthmap[self.get_char_pos(input)]
+    }
+}
+
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn fonts_test() {
+        let bitmap = [
+            0x00, 0x00, 0x5F, 0x00, 0x00, 0x00, 0x00, 0x00, // '!'
+            0x00, 0x07, 0x00, 0x07, 0x00, 0x00, 0x00, 0x00, // '"'
+            0x14, 0x7F, 0x14, 0x7F, 0x14, 0x00, 0x00, 0x00, // '#'
+            0x14, 0x7F, 0x14, 0x7F, 0x14, 0x00, 0x00, 0x00]; // '$'
+
+        let widthmap = [8,8,8,8];
+
+        let font = Font::new(8, 8, '!' as u8, '$' as u8, &bitmap, &widthmap);
+
+        let hashtag = [0x14, 0x7F, 0x14, 0x7F, 0x14, 0x00, 0x00, 0x00];
+
+        assert_eq!(font.get_char('#'), hashtag);
+
+        assert_eq!(font.get_char('$')[7], 0x00);
+
+        assert_eq!(font.get_char_width('#'), widthmap[2]);
+        assert_eq!(font.get_char_width('$'), widthmap[3]);
+    }
+
+
+
+
+    #[test]
+    fn bitmap_8x8_test() {
+        let and = [0x36, 0x49, 0x55, 0x22, 0x50, 0x00, 0x00, 0x00];
+        let zero = [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00];
+        let first_value = [0x00, 0x00, 0x5F, 0x00, 0x00, 0x00, 0x00, 0x00];
+        let last_value = [0x00, 0x41, 0x36, 0x08, 0x00, 0x00, 0x00, 0x00];
+
+		assert_eq!(bitmap_8x8('&'), and);
+
+        assert_eq!(bitmap_8x8('ß'), zero);
+        assert_eq!(bitmap_8x8('°'), zero);
+
+        assert_eq!(bitmap_8x8('!'), first_value);
+        assert_eq!(bitmap_8x8('}'), last_value);
+
+        assert_eq!(bitmap_8x8('0')[1], 0x3E);     
+    }
+}
+
+
+
+
 
-    pub(crate) fn to_bitmap(input: char) -> [u8; 8] {
+pub(crate) fn bitmap_8x8(input: char) -> [u8; 8] {
     // Populate the array with the data from the character array at the right index
     match input {
         '!' => [0x00, 0x00, 0x5F, 0x00, 0x00, 0x00, 0x00, 0x00],
@@ -100,10 +203,10 @@
 }
 /*
 pub(crate) const VCR_OSD_MONO_Bitmap = [
-  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00,
+af afa 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00,
   0xFF, 0xFF, 0xFC, 0x3F, 0xFC, 0x3F, 0xFC, 0x3F, 0xFC, 0x3F, 0xFC, 0x3F,
   0xFC, 0x3F, 0x30, 0x0C, 0x30, 0x0C, 0x00, 0x0F, 0x00, 0x00, 0xF0, 0x0F,
-  0x0F, 0x00, 0xF0, 0xF0, 0x0F, 0x0F, 0xF0, 0xF0, 0xFF, 0x0F, 0xFF, 0xF0,
+ aaa 0x0F, 0x00, 0xF0, 0xF0, 0x0F, 0x0F, 0xF0, 0xF0, 0xFF, 0x0F, 0xFF, 0xF0,
   0xFF, 0xFF, 0xFF, 0xFF, 0x0F, 0xFF, 0xF0, 0xFF, 0x0F, 0x0F, 0xF0, 0xF0,
   0x0F, 0x0F, 0x00, 0xF0, 0xF0, 0x0F, 0x0F, 0xF0, 0xF0, 0xFF, 0x0F, 0xFF,
   0xF0, 0xFF, 0xFF, 0xFF, 0xFF, 0x0F, 0xFF, 0xF0, 0xFF, 0x0F, 0x0F, 0xF0,

src/drawing/mod.rs

@@ -110,7 +110,7 @@ impl Color {
 }
 
 
-
+#[allow(dead_code)]
 pub struct Graphics {
     width: u16,
     height: u16,
@@ -184,8 +184,10 @@ impl Graphics {
     }
 
     ///TODO: implement!
+    /// TODO: use Fonts
     pub fn draw_char(&self, buffer: &mut[u8], x0: u16, y0: u16, input: char, font: &Font, color: &Color) {
         let mut counter = 0;
+        let _a = font.get_char(input);
         for &elem in font::bitmap_8x8(input).iter() {
             self.draw_byte(buffer, x0, y0 + counter * self.width, elem, color);
             counter += 1;
@@ -202,7 +204,7 @@ impl Graphics {
         }
     }
 
-    ///TODO: implement!
+    ///TODO: test!
     pub fn draw_char_8x8(&self, buffer: &mut[u8], x0: u16, y0: u16, input: char, color: &Color) {
         let mut counter = 0;
         for &elem in font::bitmap_8x8(input).iter() {
@@ -213,7 +215,7 @@ impl Graphics {
         }
     }
 
-    ///TODO: implement!
+    ///TODO: test!
     /// no autobreak line yet
     pub fn draw_string_8x8(&self, buffer: &mut[u8], x0: u16, y0: u16, input: &str, color: &Color) {
         let mut counter = 0;