Added Atari Lynx versions of three sample programs.

The Lynx target can't build the usual versions because its library doesn't have conio output and stdio.

samples/lynx/tgidemo.c

@@ -0,0 +1,179 @@
+/* Tgidemo modified for the Atari Lynx.
+**
+** Press any of the Lynx's option buttons to go to the next screen.
+*/
+
+#include <cc65.h>
+#include <conio.h>
+#include <tgi.h>
+#include <time.h>
+
+
+#define COLOR_BACK      TGI_COLOR_BLACK
+#define COLOR_FORE      TGI_COLOR_WHITE
+
+
+/*****************************************************************************/
+/*                                   Data                                    */
+/*****************************************************************************/
+
+
+
+/* Driver stuff */
+static unsigned MaxX;
+static unsigned MaxY;
+static unsigned AspectRatio;
+
+
+
+/*****************************************************************************/
+/*                                   Code                                    */
+/*****************************************************************************/
+
+
+
+/* The Lynx draws too fast.  This function delays
+** the drawing so that we can watch it.
+*/
+static void wait (unsigned char ticks)
+{
+    clock_t T = clock () + ticks;
+
+    while (clock () < T) {}
+}
+
+
+
+static void DoCircles (void)
+{
+    unsigned char I;
+    unsigned char Color = COLOR_BACK;
+    const unsigned X = MaxX / 2;
+    const unsigned Y = MaxY / 2;
+    const unsigned Limit = (X < Y) ? Y : X;
+
+    tgi_setcolor (COLOR_FORE);
+    tgi_clear ();
+
+    tgi_line (0, 0, MaxX, MaxY);
+    tgi_line (0, MaxY, MaxX, 0);
+    while (!kbhit ()) {
+        Color = (Color == COLOR_FORE) ? COLOR_BACK : COLOR_FORE;
+        tgi_setcolor (Color);
+        for (I = 10; I <= Limit; I += 10) {
+            tgi_ellipse (X, Y, I, tgi_imulround (I, AspectRatio));
+            wait (9);
+        }
+    }
+
+    cgetc ();
+}
+
+
+
+static void DoCheckerboard (void)
+{
+    unsigned X, Y;
+    unsigned char Color = COLOR_BACK;
+
+    tgi_clear ();
+
+    while (1) {
+        for (Y = 0; Y <= MaxY - 2; Y += 10) {
+            for (X = 0; X <= MaxX; X += 10) {
+                Color = (Color == COLOR_FORE) ? COLOR_BACK : COLOR_FORE;
+                tgi_setcolor (Color);
+                tgi_bar (X, Y, X+9, Y+9);
+                if (kbhit ()) {
+                    cgetc ();
+                    return;
+                }
+                wait (1);
+            }
+            Color = Color == COLOR_FORE ? COLOR_BACK : COLOR_FORE;
+        }
+        Color = Color == COLOR_FORE ? COLOR_BACK : COLOR_FORE;
+    }
+}
+
+
+
+static void DoDiagram (void)
+{
+    int XOrigin, YOrigin;
+    int Amp;
+    int X, Y;
+    unsigned I;
+
+    tgi_setcolor (COLOR_FORE);
+    tgi_clear ();
+
+    /* Determine zero and amplitude */
+    YOrigin = MaxY / 2;
+    XOrigin = 10;
+    Amp     = (MaxY - 19) / 2;
+
+    /* Y axis */
+    tgi_line (XOrigin, 10, XOrigin, MaxY-10);
+    tgi_line (XOrigin-2, 12, XOrigin, 10);
+    tgi_lineto (XOrigin+2, 12);
+
+    /* X axis */
+    tgi_line (XOrigin, YOrigin, MaxX-10, YOrigin);
+    tgi_line (MaxX-12, YOrigin-2, MaxX-10, YOrigin);
+    tgi_lineto (MaxX-12, YOrigin+2);
+
+    /* Sine */
+    tgi_gotoxy (XOrigin, YOrigin);
+    for (I = 0; I <= 360; ++I) {
+        /* Calculate the next points */
+        X = (int)(((long)(MaxX - 19) * I) / 360);
+        Y = (int)(((long)Amp * -_sin (I)) / 256);
+
+        /* Draw the line */
+        tgi_lineto (XOrigin + X, YOrigin + Y);
+    }
+
+    cgetc ();
+}
+
+
+
+static void DoLines (void)
+{
+    unsigned X;
+    const unsigned Min = (MaxX < MaxY) ? MaxX : MaxY;
+
+    tgi_setcolor (COLOR_FORE);
+    tgi_clear ();
+
+    for (X = 0; X <= Min; X += 10) {
+        tgi_line (0, 0, Min, X);
+        tgi_line (0, 0, X, Min);
+        tgi_line (Min, Min, 0, Min-X);
+        tgi_line (Min, Min, Min-X, 0);
+        wait (9);
+    }
+
+    cgetc ();
+}
+
+
+
+void main (void)
+{
+    /* Install the driver */
+    tgi_install (tgi_static_stddrv);
+    tgi_init ();
+
+    /* Get stuff from the driver */
+    MaxX = tgi_getmaxx ();
+    MaxY = tgi_getmaxy ();
+    AspectRatio = tgi_getaspectratio ();
+
+    /* Do graphics stuff */
+    DoCircles ();
+    DoCheckerboard ();
+    DoDiagram ();
+    DoLines ();
+}