From d4bf5da4809448addacd15e4d19760d5ce1b3d7e Mon Sep 17 00:00:00 2001
From: Peter Evans <pevans@activecampaign.com>
Date: Thu, 18 Jan 2018 16:21:25 -0600
Subject: [PATCH] Draw text in 40 column mode

---
 include/apple2.draw.h |  1 +
 src/apple2.c          |  1 +
 src/apple2.draw.c     | 14 ++++++++++++++
 3 files changed, 16 insertions(+)

diff --git a/include/apple2.draw.h b/include/apple2.draw.h
index 91bac59..45d9b83 100644
--- a/include/apple2.draw.h
+++ b/include/apple2.draw.h
@@ -6,5 +6,6 @@
 
 extern void apple2_draw_pixel(apple2 *, vm_16bit);
 extern void apple2_draw_text(apple2 *, vm_16bit);
+extern void apple2_draw_40col(apple2 *);
 
 #endif
diff --git a/src/apple2.c b/src/apple2.c
index ba0292e..deb6857 100644
--- a/src/apple2.c
+++ b/src/apple2.c
@@ -324,6 +324,7 @@ apple2_run_loop(apple2 *mach)
     while (vm_screen_active(mach->screen)) {
         mos6502_dis_opcode(mach->cpu, stdout, mach->cpu->PC);
         mos6502_execute(mach->cpu);
+        apple2_draw_40col(mach);
         vm_screen_refresh(mach->screen);
     }
 }
diff --git a/src/apple2.draw.c b/src/apple2.draw.c
index 9d6a815..c57e38b 100644
--- a/src/apple2.draw.c
+++ b/src/apple2.draw.c
@@ -159,3 +159,17 @@ apple2_draw_text(apple2 *mach, vm_16bit addr)
     // Now show the goddamned thing
     vm_bitfont_render(mach->sysfont, mach->screen, &dest, ch);
 }
+
+void
+apple2_draw_40col(apple2 *mach)
+{
+    size_t addr;
+
+    for (addr = 0x400; addr < 0x800; addr++) {
+        if ((addr & 0xFF) == 0x39) {
+            addr += 0x40;
+        }
+
+        apple2_draw_text(mach, addr);
+    }
+}