[Teton] Factor drawing glyphs to screen into a separate class.

sys/teton/framebuffer/console.cpp

@@ -0,0 +1,28 @@
+#include "framebuffer/console.h"
+
+void Console::WriteChar(char c) {
+  uint64_t row = cursor_pos_ / cols();
+  uint64_t fb_row = row * (psf_.height() + 1);
+  uint64_t col = cursor_pos_ % cols();
+  uint64_t fb_col = col * (psf_.width() + 1);
+
+  uint8_t* glyph = psf_.glyph(c);
+
+  for (uint8_t r = fb_row; r < fb_row + psf_.height(); r++) {
+    for (uint8_t c = fb_col; c < fb_col + psf_.width(); c++) {
+      uint8_t glyph_offset = psf_.width() - (c - fb_col) - 1;
+      if ((glyph[r] & (1 << glyph_offset))) {
+        framebuf_.DrawPixel(r, c, 0xFFFFFFF);
+      } else {
+        framebuf_.DrawPixel(r, c, 0);
+      }
+    }
+  }
+
+  cursor_pos_++;
+}
+void Console::WriteString(glcr::StringView str) {
+  for (uint64_t i = 0; i < str.size(); i++) {
+    WriteChar(str[i]);
+  }
+}