X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=src%2Fscr%2Fplasma.c;fp=src%2Fscr%2Fplasma.c;h=5caf4f4ad75f4b1e5c62ab4f5d5cf9efe4e2ad73;hb=ba648ddfc62fc6d3f47294aa8bfc10ea6ca3f479;hp=0000000000000000000000000000000000000000;hpb=3398fc6c4188104048f99b650a6cb90beda9b6ed;p=dosdemo

diff --git a/src/scr/plasma.c b/src/scr/plasma.c
new file mode 100644
index 0000000..5caf4f4
--- /dev/null
+++ b/src/scr/plasma.c
@@ -0,0 +1,111 @@
+// Just a test with a run of the mill plasma
+
+#include <stdlib.h>
+#include <math.h>
+
+#include "demo.h"
+#include "screen.h"
+
+static int init(void);
+static void destroy(void);
+static void start(long trans_time);
+static void draw(void);
+
+static struct screen scr = {
+	"plasma",
+	init,
+	destroy,
+	start,
+	0,
+	draw
+};
+
+static unsigned long startingTime;
+
+#define PSIN_SIZE 4096
+#define PPAL_SIZE 256
+
+static unsigned char *psin1, *psin2, *psin3;
+static unsigned short *plasmaPal;
+
+static unsigned short myBuffer[320 * 240];
+
+
+struct screen *plasma_screen(void)
+{
+	return &scr;
+}
+
+static int init(void)
+{
+	int i;
+
+	psin1 = (unsigned char*)malloc(sizeof(unsigned char) * PSIN_SIZE);
+	psin2 = (unsigned char*)malloc(sizeof(unsigned char) * PSIN_SIZE);
+	psin3 = (unsigned char*)malloc(sizeof(unsigned char) * PSIN_SIZE);
+
+	for (i = 0; i < PSIN_SIZE; i++)
+	{
+		psin1[i] = (unsigned char)(sin((double)i / 45.0) * 63.0 + 63.0);
+		psin2[i] = (unsigned char)(sin((double)i / 75.0) * 42.0 + 42.0);
+		psin3[i] = (unsigned char)(sin((double)i / 32.0) * 88.0 + 88.0);
+	}
+
+	plasmaPal = (unsigned short*)malloc(sizeof(unsigned short) * PPAL_SIZE);
+	for (i=0; i<PPAL_SIZE; i++)
+	{
+		int r, g, b;
+		int c = i;
+		if (c > 127) c = 255 - c;
+		c >>= 2;
+		g = 31 - c;
+		r = c;
+		b = g;
+		plasmaPal[i] = (r<<11) | (g<<5) | b;
+	}
+
+	return 0;
+}
+
+static void destroy(void)
+{
+	free(psin1);
+	free(psin2);
+	free(psin3);
+}
+
+static void start(long trans_time)
+{
+	startingTime = time_msec;
+}
+
+static void draw(void)
+{
+	int x, y;
+	unsigned char c;
+	unsigned char s1, s2;
+
+	float dt = (float)(time_msec - startingTime) / 1000.0f;
+	int t1 = sin(0.1f * dt) * 132 + 132;
+	int t2 = sin(0.2f * dt) * 248 + 248;
+	int t3 = sin(0.5f * dt) * 380 + 380;
+
+	unsigned int *vram32 = (unsigned int*)fb_pixels;
+	unsigned int p0, p1;
+	for (y = 0; y < fb_height; y++)
+	{
+		s1 = psin2[y + t2];
+		s2 = psin3[y + t1];
+		for (x = 0; x < fb_width; x+=2)
+		{
+			c = psin1[x + t1] + s1 + psin3[x + y + t3] + psin1[psin2[x + t2] + s2 + t3];
+			p0 = plasmaPal[c];
+			c = psin1[x + 1 + t1] + s1 + psin3[x + 1 + y + t3] + psin1[psin2[x + 1 + t2] + s2 + t3];
+			p1 = plasmaPal[c];
+
+			*vram32++ = (p1 << 16) | p0;
+		}
+	}
+
+	swap_buffers(0);
+}