GLUshape: Implement single primitive NxM mesh generation

2 files changed, 23 insertions, 14 deletions

diff --git a/src/mesh.c b/src/mesh.c
index 603570b..9082834 100644
--- a/src/mesh.c
+++ b/src/mesh.c
@@ -30,20 +30,32 @@ generate_triangle_mesh(unsigned rows, unsigned cols, unsigned width,
 		       mesh_end_cb *end_cb, 
 		       void *data)
 {
-	unsigned i;
-	unsigned j;
+	int i;
+	int j;
 
+	(*begin_cb)(data, GL_TRIANGLE_STRIP);
 	for (i = 0; i < rows; i++) {
-		(*begin_cb)(data, GL_TRIANGLE_STRIP);
+		if ((i & 1) == 0) {
+			for (j = 0; j < cols; j++) {
+				const unsigned e0 = ((i + 0) * width) + j;
+				const unsigned e1 = ((i + 1) * width) + j;
 
-		for (j = 0; j < cols; j++) {
-			const unsigned e0 = ((i + 0) * width) + j;
-			const unsigned e1 = ((i + 1) * width) + j;
+				(*index_cb)(data, e0);
+				(*index_cb)(data, e1);
+			}
 
-			(*index_cb)(data, e0);
-			(*index_cb)(data, e1);
-		}
+			(*index_cb)(data, (width - 1) + ((i + 0) * width));
+		} else {
+			for (j = cols - 1; j >= 0; j--) {
+				const unsigned e0 = ((i + 0) * width) + j;
+				const unsigned e1 = ((i + 1) * width) + j;
+
+				(*index_cb)(data, e0);
+				(*index_cb)(data, e1);
+			}
 
-		(*end_cb)(data);
+			(*index_cb)(data, (i + 0) * width);
+		}
 	}
+	(*end_cb)(data);
 }
diff --git a/src/sphere.cpp b/src/sphere.cpp
index 4aa1a79..c580323 100644
--- a/src/sphere.cpp
+++ b/src/sphere.cpp
@@ -98,10 +98,7 @@ GLUsphereProducer::vertex_count(void) const
 unsigned
 GLUsphereProducer::primitive_count(void) const
 {
-	/* For each slice there is a triangle strip from the north pole to the
-	 * south pole.
-	 */
-	return slices;
+	return 1;
 }