From: IrgendwerA8 <c.krueger.b@web.de>
Date: Thu, 23 Feb 2017 23:10:02 +0000 (+0100)
Subject: Improved display list instruction definition for more comfortable use within void... 
X-Git-Tag: V2.16~40^2~2
X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=ae7fa8f2ea25dbd96a062284ef77ff7b15423489;p=cc65

Improved display list instruction definition for more comfortable use within void data definition.
---

diff --git a/doc/atari.sgml b/doc/atari.sgml
index a0dbe2f47..1b084324f 100644
--- a/doc/atari.sgml
+++ b/doc/atari.sgml
@@ -317,6 +317,49 @@ chip registers.
 
 </descrip><p>
 
+<sect1>Display lists<p>
+
+An major feature of the Atari graphics chip "ANTIC" is to
+process instructions for the display generation.
+cc65 supports constructing these display lists by offering defines
+for the instructions. In conjunction with the "void"-variable extension
+of cc65, display lists can be created quite comfortable:
+
+<verb>
+...
+unsigned char ScreenMemory[100];
+
+void DisplayList =
+{
+	DL_BLK8,
+	DL_BLK8,
+	DL_BLK8,
+	DL_LMS(DL_CHR20x8x2),
+	ScreenMemory,
+	DL_CHR20x8x2,
+	DL_CHR20x8x2,
+	DL_CHR20x8x2,
+	DL_BLK4,
+	DL_CHR20x8x2,
+	DL_JVB
+};
+...
+POKEW(560,(unsigned int)&amp;DisplayList);		// SDLSTL
+...
+</verb>
+
+Please inspect the <tt/_antic.h/ header file to detemine the supported
+instruction names. Modifiers on instructions can be nested without need
+for an order:
+
+<tt/DL_LMS(DL_HSCROL(DL_VSCROL(DL_DLI(DL_MAP80x4x2))))/
+
+Please mind that ANTIC has memory alignment requirements for "player
+missile graphics"-data, font data, display lists and screen memory. Creation
+of a special linker configuration with appropriate aligned segments and
+switching to that segment in the c-code is usually neccessary. A more memory
+hungry solution consists in using the "<tt/posix_memalign()/" function in
+conjunction with copying your data to the allocated memory.
 
 <sect1>Character mapping<p>
 
diff --git a/include/_antic.h b/include/_antic.h
index ab0cd9664..23a72609c 100644
--- a/include/_antic.h
+++ b/include/_antic.h
@@ -57,42 +57,42 @@ struct __antic {
 /* antic instruction set */
 
 /* absolute instructions (non mode lines) */
-#define DL_JMP  1
-#define DL_JVB  65
+#define DL_JMP  (unsigned char) 1
+#define DL_JVB  (unsigned char) 65
 
-#define DL_BLK1 0
-#define DL_BLK2 16
-#define DL_BLK3 32
-#define DL_BLK4 48
-#define DL_BLK5 64
-#define DL_BLK6 80
-#define DL_BLK7 96
-#define DL_BLK8 112
+#define DL_BLK1 (unsigned char) 0
+#define DL_BLK2 (unsigned char) 16
+#define DL_BLK3 (unsigned char) 32
+#define DL_BLK4 (unsigned char) 48
+#define DL_BLK5 (unsigned char) 64
+#define DL_BLK6 (unsigned char) 80
+#define DL_BLK7 (unsigned char) 96
+#define DL_BLK8 (unsigned char) 112
 
 /* absolute instructions (mode lines) */
-#define DL_CHR40x8x1    2       /* monochrome, 40 character & 8 scanlines per mode line (GR. 0) */
-#define DL_CHR40x10x1   3       /* monochrome, 40 character & 10 scanlines per mode line */
-#define DL_CHR40x8x4    4       /* colour, 40 character & 8 scanlines per mode line (GR. 12) */
-#define DL_CHR40x16x4   5       /* colour, 40 character & 16 scanlines per mode line (GR. 13) */
-#define DL_CHR20x8x2    6       /* colour (duochrome per character), 20 character & 8 scanlines per mode line (GR. 1) */
-#define DL_CHR20x16x2   7       /* colour (duochrome per character), 20 character & 16 scanlines per mode line (GR. 2) */
+#define DL_CHR40x8x1    (unsigned char) 2       /* monochrome, 40 character & 8 scanlines per mode line (GR. 0) */
+#define DL_CHR40x10x1   (unsigned char) 3       /* monochrome, 40 character & 10 scanlines per mode line */
+#define DL_CHR40x8x4    (unsigned char) 4       /* colour, 40 character & 8 scanlines per mode line (GR. 12) */
+#define DL_CHR40x16x4   (unsigned char) 5       /* colour, 40 character & 16 scanlines per mode line (GR. 13) */
+#define DL_CHR20x8x2    (unsigned char) 6       /* colour (duochrome per character), 20 character & 8 scanlines per mode line (GR. 1) */
+#define DL_CHR20x16x2   (unsigned char) 7       /* colour (duochrome per character), 20 character & 16 scanlines per mode line (GR. 2) */
 
-#define DL_MAP40x8x4    8       /* colour, 40 pixel & 8 scanlines per mode line (GR. 3) */
-#define DL_MAP80x4x2    9       /* 'duochrome', 80 pixel & 4 scanlines per mode line (GR.4) */
-#define DL_MAP80x4x4    10      /* colour, 80 pixel & 4 scanlines per mode line (GR.5) */
-#define DL_MAP160x2x2   11      /* 'duochrome', 160 pixel & 2 scanlines per mode line (GR.6) */
-#define DL_MAP160x1x2   12      /* 'duochrome', 160 pixel & 1 scanline per mode line (GR.14) */
-#define DL_MAP160x2x4   13      /* 4 colours, 160 pixel & 2 scanlines per mode line (GR.7) */
-#define DL_MAP160x1x4   14      /* 4 colours, 160 pixel & 1 scanline per mode line (GR.15) */
-#define DL_MAP320x1x1   15      /* monochrome, 320 pixel & 1 scanline per mode line (GR.8) */
+#define DL_MAP40x8x4    (unsigned char) 8       /* colour, 40 pixel & 8 scanlines per mode line (GR. 3) */
+#define DL_MAP80x4x2    (unsigned char) 9       /* 'duochrome', 80 pixel & 4 scanlines per mode line (GR.4) */
+#define DL_MAP80x4x4    (unsigned char) 10      /* colour, 80 pixel & 4 scanlines per mode line (GR.5) */
+#define DL_MAP160x2x2   (unsigned char) 11      /* 'duochrome', 160 pixel & 2 scanlines per mode line (GR.6) */
+#define DL_MAP160x1x2   (unsigned char) 12      /* 'duochrome', 160 pixel & 1 scanline per mode line (GR.14) */
+#define DL_MAP160x2x4   (unsigned char) 13      /* 4 colours, 160 pixel & 2 scanlines per mode line (GR.7) */
+#define DL_MAP160x1x4   (unsigned char) 14      /* 4 colours, 160 pixel & 1 scanline per mode line (GR.15) */
+#define DL_MAP320x1x1   (unsigned char) 15      /* monochrome, 320 pixel & 1 scanline per mode line (GR.8) */
 
 /* modifiers on mode lines */
-#define DL_HSCROL       16
-#define DL_VSCROL       32
-#define DL_LMS          64
+#define DL_HSCROL(x)    (unsigned char)((x) | 16)
+#define DL_VSCROL(x)    (unsigned char)((x) | 32)
+#define DL_LMS(x)       (unsigned char)((x) | 64)
 
 /* general modifier */
-#define DL_DLI          128
+#define DL_DLI(x)       (unsigned char)((x) | 128)
 
 /* End of _antic.h */
 #endif /* #ifndef __ANTIC_H */
diff --git a/testcode/lib/atari/displaylist.c b/testcode/lib/atari/displaylist.c
new file mode 100644
index 000000000..869b5bb65
--- /dev/null
+++ b/testcode/lib/atari/displaylist.c
@@ -0,0 +1,69 @@
+/*
+** testprogram for ANTIC instructions as defined in "_antic.h"
+**
+** 23-Feb-2017, Christian Krueger
+*/
+
+#include <conio.h>
+#include <atari.h>
+#include <peekpoke.h>
+#include <string.h>
+
+// code is only for testing purposes, as screen and display list are not aligned
+// and jumps not set!
+
+unsigned char DummyScreen[400];
+
+void DisplayList = {
+	DL_BLK1,
+	DL_BLK2,
+	DL_BLK3,
+	DL_BLK4,
+	DL_BLK5,
+	DL_BLK6,
+	DL_BLK7,
+	DL_DLI(DL_BLK8),
+	DL_LMS(DL_CHR40x8x1),
+	DummyScreen,
+	DL_HSCROL(DL_CHR40x10x1),
+	DL_VSCROL(DL_CHR40x8x4),
+	DL_CHR40x16x4,
+	DL_LMS(DL_HSCROL(DL_VSCROL(DL_DLI(DL_CHR20x8x2)))),
+	DummyScreen+120,
+	DL_CHR20x16x2,
+	DL_MAP40x8x4,
+	DL_MAP80x4x2,
+	DL_MAP80x4x4,
+	DL_MAP160x2x2,
+	DL_MAP160x1x2,
+	DL_MAP160x2x4,
+	DL_MAP160x1x4,
+ 	DL_MAP320x1x1, 
+	DL_JVB,
+	DL_JMP
+};
+
+unsigned char dlend = 0;
+
+
+int
+main(void)
+{
+    // unfortunately "sizeof()" doesn't work with void data
+    // (Error: Size of data type is unknown)
+    // so we trick with the adresses at front and behind...
+
+    int returnValue = (((unsigned int)&dlend-(unsigned int)&DisplayList) != 28);  // assure only one byte per instruction!
+
+    clrscr();
+    if (returnValue)
+        cputs("Test FAILED!");
+    else
+        cputs("Test passed.");
+
+    cputs("\n\rHit any key to exit...");
+    cgetc();
+
+    return returnValue;
+}
+