wimmel_gl: Draw rects around matching subimages

All red dots in the GL rendering represent a top-left
corner of a matching rectangle.

2 files changed, 26 insertions, 17 deletions

diff --git a/Makefile b/Makefile
index 1b3255d..310f1d9 100644
--- a/Makefile
+++ b/Makefile
@@ -11,7 +11,7 @@ OBJS = wimmel.o wimmel_gl.o util.o
 all: $(PROGS)
 
 wimmel: wimmel.o util.o
-wimmel_gl: wimmel_gl.o
+wimmel_gl: wimmel_gl.o util.o
 
 .PHONY: clean all
 
diff --git a/wimmel_gl.c b/wimmel_gl.c
index 223a9de..cc08e02 100644
--- a/wimmel_gl.c
+++ b/wimmel_gl.c
@@ -6,7 +6,8 @@
 #include <GL/gl.h>
 #include <GL/glext.h>
 
-//int window = 0;
+#include "util.h"
+
 GLuint vbo;
 GLint proj_uniform, tex_uniform, pixelsize_uniform,
       search_rect_uniform, barrier_uniform;
@@ -187,6 +188,10 @@ draw(void)
 int
 main(int argc, char **argv)
 {
+	GLuint fb, rb;
+	gint stride;
+	guchar *buffer;
+
 	g_type_init();
 
 	glutInit(&argc, argv);
@@ -212,8 +217,6 @@ main(int argc, char **argv)
 	int window = glutCreateWindow("wimmel");
 	glutDestroyWindow(window);
 
-	GLuint fb, rb;
-
 	glGenFramebuffersEXT(1, &fb);
 	glGenRenderbuffersEXT(1, &rb);
 
@@ -244,24 +247,30 @@ main(int argc, char **argv)
 
 	glPixelStorei(GL_PACK_ALIGNMENT, 2);
 
-	gint stride = width * 4;
-	guchar *buffer = malloc(stride * height);
+	stride = width * 4;
+	buffer = malloc(stride * height);
 	glReadPixels(0, 0, width, height,
 		     GL_RGBA, GL_UNSIGNED_BYTE,
 		     buffer);
 
-	GdkPixbuf *t_output, *output;
-
-	t_output = gdk_pixbuf_new_from_data(buffer,
-					  GDK_COLORSPACE_RGB,
-					  TRUE, 8,
-					  width, height, stride,
-					  NULL, NULL);
-	output = gdk_pixbuf_flip(t_output, FALSE);
+	for (int j = 0; j < height; ++j) {
+		guchar *row = buffer + (height - 1 - j) * stride;
+		for (int i = 0; i < width; ++i) {
+			if (*(row + i*4)) {
+				color_t color = COLOR(255, 0, 0, 0);
+				for (int k = i; k < i+mwidth; k++) {
+					put_pixel(pixbuf, POINT(k, j), color);
+					put_pixel(pixbuf, POINT(k, j+mheight), color);
+				}
+				for (int n = j; n < j+mheight; n++) {
+					put_pixel(pixbuf, POINT(i, n), color);
+					put_pixel(pixbuf, POINT(i+mwidth, n), color);
+				}
+			}
+		}
+	}
 
-	gdk_pixbuf_save(output, "output_gl.png", "png", NULL, NULL);
-	g_object_unref(output);
-	g_object_unref(t_output);
+	gdk_pixbuf_save(pixbuf, "output_gl.png", "png", NULL, NULL);
 	free(buffer);
 	g_object_unref(pixbuf);