Fix UVs, change tables to use OpenGL convention...

cube_tables.cpp

@@ -9,9 +9,9 @@ namespace Cube {
 //  / |     / |  Corners
 // 4-------5  |
 // |  3----|--2
-// | /     | /   y z
-// |/      |/    |/
-// 0-------1     o--x
+// | /     | /     y z
+// |/      |/      |/   OpenGL axis convention
+// 0-------1    x--o
 //
 //
 //     o---10----o
@@ -29,47 +29,37 @@ namespace Cube {
 // Edges are ordered according to the Voxel::Edge enum (only g_edge_inormals!).
 //
 
-//static const unsigned int CORNER_COUNT = 8;
-//static const unsigned int EDGE_COUNT = 12;
-
-// Order doesn't technically matter here, they are for reading convenience.
-// If you need a special ordering, combine index with other tables
+// Ordered as per the cube corners diagram
 const Vector3 g_corner_position[CORNER_COUNT] = {
-	Vector3(0, 0, 0),
 	Vector3(1, 0, 0),
-	Vector3(1, 0, 1),
+	Vector3(0, 0, 0),
 	Vector3(0, 0, 1),
-	Vector3(0, 1, 0),
+	Vector3(1, 0, 1),
 	Vector3(1, 1, 0),
-	Vector3(1, 1, 1),
-	Vector3(0, 1, 1)
+	Vector3(0, 1, 0),
+	Vector3(0, 1, 1),
+	Vector3(1, 1, 1)
 };
 
 const int g_side_quad_triangles[SIDE_COUNT][6] = {
-	// LEFT
-	{ 0, 1, 2, 0, 2, 3 },
-	// RIGHT
-	{ 0, 1, 2, 0, 2, 3 },
-	// BOTTOM
-	{ 0, 1, 2, 0, 2, 3 },
-	// TOP
-	{ 0, 1, 2, 0, 2, 3 },
-	// BACK
-	{ 0, 1, 2, 0, 2, 3 },
-	// FRONT
-	{ 0, 1, 2, 0, 2, 3 },
+	{ 0, 2, 1, 0, 3, 2 }, // LEFT (+x)
+	{ 0, 2, 1, 0, 3, 2 }, // RIGHT (-x)
+	{ 0, 2, 1, 0, 3, 2 }, // BOTTOM (-y)
+	{ 0, 2, 1, 0, 3, 2 }, // TOP (+y)
+	{ 0, 2, 1, 0, 3, 2 }, // BACK (-z)
+	{ 0, 2, 1, 0, 3, 2 }, // FRONT (+z)
 };
 
-const unsigned int g_side_coord[SIDE_COUNT] = { 0, 0, 1, 1, 2, 2 };
-const unsigned int g_side_sign[SIDE_COUNT] = { 0, 1, 0, 1, 0, 1 };
+//const unsigned int g_side_coord[SIDE_COUNT] = { 0, 0, 1, 1, 2, 2 };
+//const unsigned int g_side_sign[SIDE_COUNT] = { 0, 1, 0, 1, 0, 1 };
 
 const Vector3i g_side_normals[SIDE_COUNT] = {
-	Vector3i(-1, 0, 0),
-	Vector3i(1, 0, 0),
-	Vector3i(0, -1, 0),
-	Vector3i(0, 1, 0),
-	Vector3i(0, 0, -1),
-	Vector3i(0, 0, 1),
+	Vector3i(1, 0, 0), // LEFT
+	Vector3i(-1, 0, 0), // RIGHT
+	Vector3i(0, -1, 0), // BOTTOM
+	Vector3i(0, 1, 0), // TOP
+	Vector3i(0, 0, -1), // BACK
+	Vector3i(0, 0, 1), // FRONT
 };
 
 // Corners have same winding, relative to the face's normal
@@ -104,32 +94,32 @@ const unsigned int g_side_edges[SIDE_COUNT][4] = {
 //};
 
 const Vector3i g_corner_inormals[CORNER_COUNT] = {
-	Vector3i(-1, -1, -1),
 	Vector3i(1, -1, -1),
-	Vector3i(1, -1, 1),
+	Vector3i(-1, -1, -1),
 	Vector3i(-1, -1, 1),
+	Vector3i(1, -1, 1),
 
-	Vector3i(-1, 1, -1),
 	Vector3i(1, 1, -1),
-	Vector3i(1, 1, 1),
-	Vector3i(-1, 1, 1)
+	Vector3i(-1, 1, -1),
+	Vector3i(-1, 1, 1),
+	Vector3i(1, 1, 1)
 };
 
 const Vector3i g_edge_inormals[EDGE_COUNT] = {
 	Vector3i(0, -1, -1),
-	Vector3i(1, -1, 0),
-	Vector3i(0, -1, 1),
 	Vector3i(-1, -1, 0),
+	Vector3i(0, -1, 1),
+	Vector3i(1, -1, 0),
 
-	Vector3i(-1, 0, -1),
 	Vector3i(1, 0, -1),
-	Vector3i(1, 0, 1),
+	Vector3i(-1, 0, -1),
 	Vector3i(-1, 0, 1),
+	Vector3i(1, 0, 1),
 
 	Vector3i(0, 1, -1),
-	Vector3i(1, 1, 0),
+	Vector3i(-1, 1, 0),
 	Vector3i(0, 1, 1),
-	Vector3i(-1, 1, 0)
+	Vector3i(1, 1, 0)
 };
 
 const unsigned int g_edge_corners[EDGE_COUNT][2] = {

cube_tables.h

@@ -54,8 +54,8 @@ extern const Vector3 g_corner_position[CORNER_COUNT];
 
 extern const int g_side_quad_triangles[SIDE_COUNT][6];
 
-extern const unsigned int g_side_coord[SIDE_COUNT];
-extern const unsigned int g_side_sign[SIDE_COUNT];
+//extern const unsigned int g_side_coord[SIDE_COUNT];
+//extern const unsigned int g_side_sign[SIDE_COUNT];
 
 extern const Vector3i g_side_normals[SIDE_COUNT];
 

voxel.cpp

@@ -220,14 +220,19 @@ void Voxel::update_cube_uv_sides() {
 	}
 
 	float e = 0.001;
+	// Winding is the same as the one chosen in Cube:: vertices
+	// I am confused. I read in at least 3 OpenGL tutorials that texture coordinates start at bottom-left (0,0).
+	// But even though Godot is said to follow OpenGL's convention, the engine starts at top-left!
 	const Vector2 uv[4] = {
-		Vector2(e, e),
-		Vector2(1.f - e, e),
-		Vector2(1.f - e, 1.f - e),
 		Vector2(e, 1.f - e),
+		Vector2(1.f - e, 1.f - e),
+		Vector2(1.f - e, e),
+		Vector2(e, e),
 	};
 
-	float s = 1.0 / (float)library->get_atlas_size();
+	float atlas_size = (float)library->get_atlas_size();
+	CRASH_COND(atlas_size <= 0);
+	float s = 1.0 / atlas_size;
 
 	for (unsigned int side = 0; side < Cube::SIDE_COUNT; ++side) {
 		_model_side_uvs[side].resize(4);

voxel_mesher.cpp

@@ -131,8 +131,8 @@ Array VoxelMesher::build(const VoxelBuffer &buffer, unsigned int channel, Vector
 	int deck_size = buffer.get_size().x * row_size;
 
 	int side_neighbor_lut[Cube::SIDE_COUNT];
-	side_neighbor_lut[Cube::SIDE_LEFT] = -row_size;
-	side_neighbor_lut[Cube::SIDE_RIGHT] = row_size;
+	side_neighbor_lut[Cube::SIDE_LEFT] = row_size;
+	side_neighbor_lut[Cube::SIDE_RIGHT] = -row_size;
 	side_neighbor_lut[Cube::SIDE_BACK] = -deck_size;
 	side_neighbor_lut[Cube::SIDE_FRONT] = deck_size;
 	side_neighbor_lut[Cube::SIDE_BOTTOM] = -1;
@@ -363,6 +363,14 @@ Array VoxelMesher::build(const VoxelBuffer &buffer, unsigned int channel, Vector
 		const Arrays &arrays = _arrays[i];
 		if (arrays.positions.size() != 0) {
 
+			/*print_line("Arrays:");
+			for(int i = 0; i < arrays.positions.size(); ++i)
+				print_line(String("  P {0}").format(varray(arrays.positions[i])));
+			for(int i = 0; i < arrays.normals.size(); ++i)
+				print_line(String("  N {0}").format(varray(arrays.normals[i])));
+			for(int i = 0; i < arrays.uvs.size(); ++i)
+				print_line(String("  UV {0}").format(varray(arrays.uvs[i])));*/
+
 			Array mesh_arrays;
 			mesh_arrays.resize(Mesh::ARRAY_MAX);