7491 - baremetal: draw ASCII text to screen

baremetal/313index-bounds-check.subx

@@ -0,0 +1,11 @@
+# TODO: bring this back
+
+__check-mu-array-bounds:  # index: int, elem-size: int, arr-size: int, function-name: (addr array byte), array-name: (addr array byte)
+    # . prologue
+    55/push-ebp
+    89/<- %ebp 4/r32/esp
+$__check-mu-array-bounds:end:
+    # . epilogue
+    89/<- %esp 5/r32/ebp
+    5d/pop-to-ebp
+    c3/return

baremetal/401draw-text-rightward.mu

@@ -0,0 +1,16 @@
+fn draw-text-rightward screen: (addr screen), _text: (addr array byte), x: int, y: int, color: int {
+  var text/esi: (addr array byte) <- copy _text
+  var len/ecx: int <- length text
+  var i/edx: int <- copy 0
+  {
+    compare i, len
+    break-if->=
+    var g/eax: (addr byte) <- index text, i
+    var g2/eax: byte <- copy-byte *g
+    var g3/eax: grapheme <- copy g2
+    draw-grapheme screen, g3, x, y, color
+    add-to x, 8  # font-width
+    i <- increment
+    loop
+  }
+}

baremetal/ex5.mu

@@ -0,0 +1,14 @@
+# Draw an ASCII string using the built-in font (GNU unifont)
+#
+# To build a disk image:
+#   ./translate_mu_baremetal baremetal/ex5.mu     # emits disk.img
+# To run:
+#   qemu-system-i386 disk.img
+# Or:
+#   bochs -f baremetal/boot.bochsrc               # boot.bochsrc loads disk.img
+#
+# Expected output: text in green near the top-left corner of screen
+
+fn main {
+  draw-text-rightward 0, "hello from baremetal Mu!", 0x10, 0x10, 0xa
+}