1 files changed, 89 insertions, 0 deletions
diff --git a/Plugins/modgain.c b/Plugins/modgain.c
new file mode 100644
index 0000000..1c4ce56
--- /dev/null
+++ b/Plugins/modgain.c
@@ -0,0 +1,89 @@
+// 242.modgain -- does modulo channel shifting on an input image.
+//		by r. luke dubois (luke@music.columbia.edu),
+//			computer music center, columbia university, 2001.
+//
+//  Pd / Framestein port by Olaf Matthes <olaf.matthes@gmx.de>, June 2002
+//
+//	objects and source are provided without warranty of any kind, express or implied.
+//
+//  usage: modgain <red> <green> <blue>
+//
+
+#include <stdio.h>
+#include <string.h>
+#include <math.h>
+#include "plugin.h"
+
+void perform_effect(struct frame f, struct args arg)
+{
+	int x,y;
+	int red, green, blue, alpha;    // parameters
+	byte r, g, b, a;
+	byte bits = f.pixelformat/8;
+	byte redpix, greenpix, bluepix;	// the color values
+	pixel16 *c16;
+	pixel24 *c24;
+	pixel32 *c32;
+	char *t;
+
+	// get params
+	if(!arg.s) return;
+	red = atoi(arg.s);
+	if(!(t = strstr(arg.s, " "))) return;
+	green = atoi(t+1);
+	if(!(t = strstr(arg.s, " "))) return;
+	blue = atoi(t+1);
+
+	printf("modgain: r%d g%d b%d\n", red, green, blue);
+
+	for(y = 0; y < f.height; y++) 
+	{
+		for(x = 0; x < f.width; x++)
+		{
+			switch(f.pixelformat)
+			{
+				case 16:
+					c16 = scanline16(f, y);
+					r = (r16(c16[x]) + red) % 255;
+					g = (g16(c16[x]) + green) % 255;
+					b = (b16(c16[x]) + blue) % 255;
+						// shift the pixels and wrap them
+					if(r<0) r += 255;
+					if(g<0) g += 255;
+					if(b<0) b += 255;
+
+					c16[x] = rgbtocolor16(r, g, b);
+					break;
+				case 24:
+					c24 = scanline24(f, y);
+					r = (r24(c24[x]) + red) % 255;
+					g = (g24(c24[x]) + green) % 255;
+					b = (b24(c24[x]) + blue) % 255;
+						// shift the pixels and wrap them
+					if(r<0) r += 255;
+					if(g<0) g += 255;
+					if(b<0) b += 255;
+
+					c24[x] = rgbtocolor24(r, g, b);
+					break;
+				case 32:
+					c32 = scanline32(f, y);
+					r = (r32(c32[x]) + red) % 255;
+					g = (g32(c32[x]) + green) % 255;
+					b = (b32(c32[x]) + blue) % 255;
+						// shift the pixels and wrap them
+					if(r<0) r += 255;
+					if(g<0) g += 255;
+					if(b<0) b += 255;
+
+					c32[x] = rgbtocolor32(r, g, b);
+					break;
+			}
+		}
+	}
+}
+
+void perform_copy(struct frame f1, struct frame f2, struct args a)
+{
+	printf("Using modgain as copy operation does nothing!\n");
+}