From 32f99ca5d917edecc406a28d3903feadbfd7afde Mon Sep 17 00:00:00 2001
From: Adam Greenwood-Byrne <adam@isometim.es>
Date: Fri, 16 Apr 2021 20:28:59 +0100
Subject: [PATCH] Added samples/wgt36.c and wgt/wxor.c

---
 part12-wgt/include/wgt.h   |  1 +
 part12-wgt/samples/wgt36.c | 96 ++++++++++++++++++++++++++++++++++++++
 part12-wgt/wgt/wxor.c      | 42 +++++++++++++++++
 3 files changed, 139 insertions(+)
 create mode 100644 part12-wgt/samples/wgt36.c
 create mode 100644 part12-wgt/wgt/wxor.c

diff --git a/part12-wgt/include/wgt.h b/part12-wgt/include/wgt.h
index 4a2ff05..c4bd5cd 100644
--- a/part12-wgt/include/wgt.h
+++ b/part12-wgt/include/wgt.h
@@ -158,3 +158,4 @@ void msetxy (short x, short y);
 void msetbut (short event, short bnum);
 void msetbounds (short x1, short y1, short x2, short y2);
 void noclick();
+void wxorbox (short x, short y, short x2, short y2, unsigned char col);
diff --git a/part12-wgt/samples/wgt36.c b/part12-wgt/samples/wgt36.c
new file mode 100644
index 0000000..99185af
--- /dev/null
+++ b/part12-wgt/samples/wgt36.c
@@ -0,0 +1,96 @@
+#include "include/wgt.h"
+#include "include/mem.h"
+#include "include/multicore.h"
+
+// ######## REQUIRED FUNCTIONS ########
+
+unsigned long state0 = 1000;
+unsigned long state1 = 2000;
+
+unsigned long rand(void)
+{
+    unsigned long s1 = state0;
+    unsigned long s0 = state1;
+
+    state0 = s0;
+    s1 ^= s1 << 23;
+    s1 ^= s1 >> 17;
+    s1 ^= s0;
+    s1 ^= s0 >> 26;
+    state1 = s1;
+
+    return state0 + state1;
+}
+
+// ######## STUB FUNCTIONS ########
+
+unsigned int kb = 0;
+
+unsigned int kbhit(void) {
+    kb++;
+    return kb / 500;
+}
+
+void getch(void) {
+    wait_msec(0x500000);
+    kb = 0;
+}
+
+// ######## WGT EXAMPLES ########
+
+#define NUM_IN 5       /* number of random points */
+#define NUM_OUT 30     /* number of points of bezier curve */
+/* Fewer points will make more chunky line */
+
+int ox, oy;  /* old mouse coordinates */
+int i;
+
+void wgt36()
+{
+  set_clock_rate(get_max_clock());
+  mem_init();
+  vga256 ();			/* Initialize graphics mode */
+
+  start_core2(minit);           // Start the comms engine (core 2)
+  while (!comms_up);            // Wait for comms up
+
+  for (i = 0; i < 200; i++) /* Draw a background */
+    {
+     wsetcolor (vgapal[i]);
+     wline (0, i, 319, i);
+    }
+
+  do {  /* Draws a filled xorbox using mouse coordinates as one corner. */
+   ox = mx;
+   oy = my;
+   wxorbox (50, 50, ox, oy, vgapal[128]);    /* Draw the box */
+   while ((mx == ox) && (my == oy) && (!but));  /* Do nothing while mouse is
+						  stationary. */
+   wxorbox (50, 50, ox, oy, vgapal[128]);
+   /* Erase the box by drawing the same thing */
+  } while (but == 0);
+
+  noclick ();
+
+  do {  /* Draws a hollow rubber box using mouse coordinates as one corner. */
+   ox = mx;
+   oy = my;
+   wxorbox (50, 50, ox, 50, vgapal[128]);
+   wxorbox (ox, 50, ox, oy, vgapal[128]);    /* Draw the box */
+   wxorbox (50, oy, ox, oy, vgapal[128]);
+   wxorbox (50, 50, 50, oy, vgapal[128]);
+   while ((mx == ox) && (my == oy) && (!but));  /* Do nothing while mouse is
+						   stationary. */
+   wxorbox (50, 50, ox, 50, vgapal[128]);
+   wxorbox (ox, 50, ox, oy, vgapal[128]);    /* Erase the box */
+   wxorbox (50, oy, ox, oy, vgapal[128]);
+   wxorbox (50, 50, 50, oy, vgapal[128]);
+  } while (but == 0);
+  mdeinit ();                   /* Deinitialize the mouse handler */
+}
+
+void main()
+{
+    wgt36();
+    while (1);
+}
diff --git a/part12-wgt/wgt/wxor.c b/part12-wgt/wgt/wxor.c
new file mode 100644
index 0000000..ec4a364
--- /dev/null
+++ b/part12-wgt/wgt/wxor.c
@@ -0,0 +1,42 @@
+#include "../include/wgt.h"
+
+void wxorbox (short x, short y, short x2, short y2, unsigned char col)
+{
+  short i, j;                          /* Loop Control */
+  block temp;                          /* Temp pointer to screen */
+
+  if  (y2 < y)
+  {
+    /* swap y's */
+    i = y;
+    y = y2;
+    y2 = i;
+  }
+
+  if  (x2 < x)
+  {
+    /* swap x's */
+    i = x;
+    x = x2;
+    x2 = i;
+  }
+
+  if  (y2 > by) y2 = by;             /* Clip box */
+  if  (x2 > bx) x2 = bx;
+  if  (y < ty) y = ty;
+  if  (x < tx) x = tx;
+
+  temp = &abuf[y*WGT_SYS.xres + x];             /* Move to first offset */
+
+  for  (j = y; j <= y2; j++)
+  {
+    for  (i = x; i <= x2; i++)
+    {
+      /* This can be change to perform any logical operation
+      on the pixels, such as & or | */
+      *temp = *temp ^ col;             /* XOR the pixel on screen with col and put it back on screen */
+      temp++;                          /* Go to next pixel */
+    }                                  /* x loop */
+    temp += (WGT_SYS.xres - 1) - (x2 - x);            /* Advance to next row */
+  }                                    /* y loop */
+}