From af94a88e5de76c4b00df102f82643b4b64cb529a Mon Sep 17 00:00:00 2001
From: John Tsiombikas <nuclear@mutantstargoat.com>
Date: Thu, 26 Jul 2018 19:35:16 +0300
Subject: [PATCH] conv_sprite tool

---
 tools/conv_sprite   |   13 ++++++++
 tools/conv_sprite.c |   90 +++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 103 insertions(+)
 create mode 100755 tools/conv_sprite
 create mode 100644 tools/conv_sprite.c

diff --git a/tools/conv_sprite b/tools/conv_sprite
new file mode 100755
index 0000000..c05deb7
--- /dev/null
+++ b/tools/conv_sprite
@@ -0,0 +1,13 @@
+#!/bin/sh
+
+if [ -z "$1" ]; then
+	echo "pass the sprite header file as argument"
+	exit 1
+fi
+
+cc -pedantic -Wall -DHDRFILE=\"$1\" -o /tmp/conv_sprite.bin conv_sprite.c
+if [ $? != 0 ]; then
+	exit 1
+fi
+
+/tmp/conv_sprite.bin
diff --git a/tools/conv_sprite.c b/tools/conv_sprite.c
new file mode 100644
index 0000000..ff50a6a
--- /dev/null
+++ b/tools/conv_sprite.c
@@ -0,0 +1,90 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+
+#include HDRFILE
+
+#define MAX_SPRITE_WIDTH	16
+
+static void conv_sprite(int slice, unsigned char *img, int width, int height, int pitch);
+static void conv_img_data(int sub, uint16_t *out, unsigned char *img, int width,
+		int height, int pitch);
+
+int main(int argc, char **argv)
+{
+	int i, nslices;
+
+	nslices = (width + MAX_SPRITE_WIDTH - 1) / MAX_SPRITE_WIDTH;
+	fprintf(stderr, "source image: %dx%d. splitting into %d slices\n",
+			width, height, nslices);
+
+	printf("\t.data\n\n");
+
+	for(i=0; i<nslices; i++) {
+		int xstart = i * MAX_SPRITE_WIDTH;
+		int spr_w = width - xstart;
+		if(spr_w > MAX_SPRITE_WIDTH) spr_w = MAX_SPRITE_WIDTH;
+
+		conv_sprite(i, header_data + xstart, spr_w, height, width);
+	}
+
+	printf("\n\t.global sprpal\n");
+	printf("sprpal:\n");
+	for(i=0; i<16; i++) {
+		int r = header_data_cmap[i][0] >> 4;
+		int g = header_data_cmap[i][1] >> 4;
+		int b = header_data_cmap[i][2] >> 4;
+		unsigned int col = ((r & 0xf) << 8) | ((g & 0xf) << 4) | (b & 0xf);
+		printf("\t.short 0x%03x\n", col);
+	}
+}
+
+static void conv_sprite(int slice, unsigned char *img, int width, int height, int pitch)
+{
+	int i, j;
+	uint16_t *sprdata;
+
+	for(i=0; i<2; i++) {
+		printf("\n\t.global spr%d%c\n", slice, i == 0 ? 'a' : 'b');
+		printf("spr%d%c:\n", slice, i == 0 ? 'a' : 'b');
+		printf("\t.short 0\n");		/* position x/y */
+		printf("\t.short 0\n");		/* vstop */
+
+		sprdata = malloc(height * 2 * sizeof *sprdata);
+		conv_img_data(i, sprdata, img, width, height, pitch);
+
+		for(j=0; j<height; j++) {
+			printf("\t.short 0x%x\n", (unsigned int)sprdata[j]);
+		}
+
+		printf("\t.long 0\n");	/* end of sprite CW */
+		free(sprdata);
+	}
+}
+
+static void conv_img_data(int sub, uint16_t *out, unsigned char *img, int width,
+		int height, int pitch)
+{
+	int i, j, inshift;
+	uint16_t bit0, bit1;
+
+	/* sprite 0: low order bits, sprite 1: high order bits */
+	inshift = sub == 0 ? 0 : 2;
+
+	for(i=0; i<height; i++) {
+		bit0 = bit1 = 0;
+		for(j=0; j<width; j++) {
+			bit0 = (bit0 << 1) | ((img[j] >> inshift) & 1);
+			bit1 = (bit1 << 1) | ((img[j] >> (inshift + 1)) & 1);
+		}
+		if(width < MAX_SPRITE_WIDTH) {
+			bit0 <<= MAX_SPRITE_WIDTH - width;
+			bit1 <<= MAX_SPRITE_WIDTH - width;
+		}
+		*out++ = bit0;
+		*out++ = bit1;
+		img += pitch;
+	}
+}
+
-- 
1.7.10.4