Merge pull request #6 from clij/watershed

add macro for drawing a grid

src/main/macro/grid.ijm

@@ -0,0 +1,54 @@
+// grid_GPU.ijm 
+// 
+// Draws a grid in an emppty image on the GPU.
+// You need to install this update sites in Fiji:
+//  * clij
+//  * clij2
+//
+// Author: Robert Haase, rhaase@mpi-cbg.de
+//         November 2019
+//------------------------------------------------
+
+// image size
+width = 1000;
+height = 1000;
+
+// grid config
+gridspacing = 50;
+thickness = 1.1;
+
+// define the image name
+image = "image";
+
+// initialize GPU
+run("CLIJ Macro Extensions", "cl_device=[Intel(R) UHD Graphics 620]");
+
+// create an empty image on the GPU
+Ext.CLIJ_create2D(image, width, height, 8);
+
+// initialize the image with zeros
+Ext.CLIJ_set(image, 0);
+
+for(x = 0; x < width; x += gridspacing) {
+	for(y = 0; y < height; y += gridspacing) {
+		// vertical line
+		x1 = x;
+		x2 = x;
+		y1 = 0;
+		y2 = height;
+		z1 = 0;
+		z2 = 0;
+		Ext.CLIJx_drawLine(image, x1, y1, z1, x2, y2, z2, thickness);
+
+		// horizontal line
+		x1 = 0;
+		x2 = width;
+		y1 = y;
+		y2 = y;
+		z1 = 0;
+		z2 = 0;
+		Ext.CLIJx_drawLine(image, x1, y1, z1, x2, y2, z2, thickness);
+	}
+}
+Ext.CLIJ_pull(image);
+