From: Daniel Karbach <daniel.karbach@localhorst.tv>
Date: Wed, 11 Mar 2015 20:43:52 +0000 (+0100)
Subject: don't add obstructed blocks to meshes
X-Git-Url: https://git.localhorst.tv/?a=commitdiff_plain;h=a58c4558e7d4934f4d0ee621520acfe1c8258c93;p=blank.git

don't add obstructed blocks to meshes
---

diff --git a/src/block.cpp b/src/block.cpp
index cdfc452..236a61f 100644
--- a/src/block.cpp
+++ b/src/block.cpp
@@ -5,6 +5,16 @@ namespace blank {
 
 const NullShape BlockType::DEFAULT_SHAPE;
 
+BlockType::BlockType(bool v, const glm::vec3 &col, const Shape *s)
+: shape(s)
+, color(col)
+, outline_color(-1, -1, -1)
+, id(0)
+, visible(v)
+, fill({ false, false, false, false, false, false }) {
+
+}
+
 void BlockType::FillModel(
 	Model::Buffer &buf,
 	const glm::vec3 &pos_offset,
diff --git a/src/block.hpp b/src/block.hpp
index 1663c16..967cc1f 100644
--- a/src/block.hpp
+++ b/src/block.hpp
@@ -28,20 +28,28 @@ struct Block {
 /// attributes of a type of block
 struct BlockType {
 
+	const Shape *shape;
+	glm::vec3 color;
+	glm::vec3 outline_color;
+
 	Block::Type id;
 
 	bool visible;
 
-	const Shape *shape;
-	glm::vec3 color;
-	glm::vec3 outline_color;
+	struct Faces {
+		bool right;
+		bool left;
+		bool top;
+		bool bottom;
+		bool front;
+		bool back;
+	} fill;
 
 	explicit BlockType(
 		bool v = false,
 		const glm::vec3 &color = { 1, 1, 1 },
-		const Shape *shape = &DEFAULT_SHAPE,
-		const glm::vec3 &outline_color = { -1, -1, -1 })
-	: id(0), visible(v), shape(shape), color(color), outline_color(outline_color) { }
+		const Shape *shape = &DEFAULT_SHAPE
+	);
 
 	static const NullShape DEFAULT_SHAPE;
 
diff --git a/src/chunk.cpp b/src/chunk.cpp
index bed947e..16ff4e5 100644
--- a/src/chunk.cpp
+++ b/src/chunk.cpp
@@ -137,6 +137,8 @@ void Chunk::Update() {
 
 	Model::Index vtx_counter = 0;
 	for (size_t i = 0; i < Size(); ++i) {
+		if (Obstructed(i)) continue;
+
 		const BlockType &type = Type(blocks[i]);
 		type.FillModel(buf, ToCoords(i), vtx_counter);
 		vtx_counter += type.shape->VertexCount();
@@ -146,6 +148,34 @@ void Chunk::Update() {
 	dirty = false;
 }
 
+bool Chunk::Obstructed(int idx) const {
+	if (IsBorder(idx)) return false;
+
+	// not checking neighbor visibility here, so all
+	// invisible blocks must have their fill set to 6x false
+	// (the default, so should be okay)
+
+	const BlockType &right = Type(blocks[idx + 1]);
+	if (!right.fill.left) return false;
+
+	const BlockType &left = Type(blocks[idx - 1]);
+	if (!left.fill.right) return false;
+
+	const BlockType &top = Type(blocks[idx + Width()]);
+	if (!top.fill.bottom) return false;
+
+	const BlockType &bottom = Type(blocks[idx - Width()]);
+	if (!bottom.fill.top) return false;
+
+	const BlockType &front = Type(blocks[idx + Width() * Height()]);
+	if (!front.fill.back) return false;
+
+	const BlockType &back = Type(blocks[idx - Width() * Height()]);
+	if (!back.fill.front) return false;
+
+	return true;
+}
+
 
 ChunkLoader::ChunkLoader(const BlockTypeRegistry &reg, const Generator &gen)
 : base(0, 0, 0)
diff --git a/src/chunk.hpp b/src/chunk.hpp
index e442e4e..e27cf5e 100644
--- a/src/chunk.hpp
+++ b/src/chunk.hpp
@@ -52,6 +52,17 @@ public:
 		);
 	}
 
+	static constexpr bool IsBorder(int idx) {
+		return
+			idx < Width() * Height() ||
+			(idx / Width()) % Height() == 0 ||
+			(idx / Width()) % Height() == Height() - 1 ||
+			(idx / (Width() * Height())) == Depth() - 1;
+	}
+
+	// check if block at given index is completely enclosed (and therefore invisible)
+	bool Obstructed(int idx) const;
+
 	void Allocate();
 	void Invalidate() { dirty = true; }
 
diff --git a/src/world.cpp b/src/world.cpp
index 248685c..46abf71 100644
--- a/src/world.cpp
+++ b/src/world.cpp
@@ -14,18 +14,73 @@ World::World()
 , generate(0)
 , chunks(blockType, generate)
 , player() {
-	blockType.Add(BlockType{ true, { 1.0f, 1.0f, 1.0f }, &blockShape }); // white block
-	blockType.Add(BlockType{ true, { 1.0f, 1.0f, 1.0f }, &stairShape }); // white stair
-	blockType.Add(BlockType{ true, { 1.0f, 1.0f, 1.0f }, &slabShape }); // white slab
-	blockType.Add(BlockType{ true, { 1.0f, 0.0f, 0.0f }, &blockShape }); // red block
-	blockType.Add(BlockType{ true, { 1.0f, 0.0f, 0.0f }, &stairShape }); // red stair
-	blockType.Add(BlockType{ true, { 1.0f, 0.0f, 0.0f }, &slabShape }); // red slab
-	blockType.Add(BlockType{ true, { 0.0f, 1.0f, 0.0f }, &blockShape }); // green block
-	blockType.Add(BlockType{ true, { 0.0f, 1.0f, 0.0f }, &stairShape }); // green stair
-	blockType.Add(BlockType{ true, { 0.0f, 1.0f, 0.0f }, &slabShape }); // green slab
-	blockType.Add(BlockType{ true, { 0.0f, 0.0f, 1.0f }, &blockShape }); // blue block
-	blockType.Add(BlockType{ true, { 0.0f, 0.0f, 1.0f }, &stairShape }); // blue stair
-	blockType.Add(BlockType{ true, { 0.0f, 0.0f, 1.0f }, &slabShape }); // blue slab
+	BlockType::Faces block_fill = {  true,  true,  true,  true,  true,  true };
+	BlockType::Faces slab_fill  = { false, false, false,  true, false, false };
+	BlockType::Faces stair_fill = {  true, false, false,  true, false, false };
+
+	{ // white block
+		BlockType type(true, { 1.0f, 1.0f, 1.0f }, &blockShape);
+		type.fill = block_fill;
+		blockType.Add(type);
+	}
+	{ // white slab
+		BlockType type(true, { 1.0f, 1.0f, 1.0f }, &slabShape);
+		type.fill = slab_fill;
+		blockType.Add(type);
+	}
+	{ // white stair
+		BlockType type(true, { 1.0f, 1.0f, 1.0f }, &stairShape);
+		type.fill = stair_fill;
+		blockType.Add(type);
+	}
+
+	{ // red block
+		BlockType type(true, { 1.0f, 0.0f, 0.0f }, &blockShape);
+		type.fill = block_fill;
+		blockType.Add(type);
+	}
+	{ // red slab
+		BlockType type(true, { 1.0f, 0.0f, 0.0f }, &slabShape);
+		type.fill = slab_fill;
+		blockType.Add(type);
+	}
+	{ // red stair
+		BlockType type(true, { 1.0f, 0.0f, 0.0f }, &stairShape);
+		type.fill = stair_fill;
+		blockType.Add(type);
+	}
+
+	{ // green block
+		BlockType type(true, { 0.0f, 1.0f, 0.0f }, &blockShape);
+		type.fill = block_fill;
+		blockType.Add(type);
+	}
+	{ // green slab
+		BlockType type(true, { 0.0f, 1.0f, 0.0f }, &slabShape);
+		type.fill = slab_fill;
+		blockType.Add(type);
+	}
+	{ // green stair
+		BlockType type(true, { 0.0f, 1.0f, 0.0f }, &stairShape);
+		type.fill = stair_fill;
+		blockType.Add(type);
+	}
+
+	{ // blue block
+		BlockType type(true, { 0.0f, 0.0f, 1.0f }, &blockShape);
+		type.fill = block_fill;
+		blockType.Add(type);
+	}
+	{ // blue slab
+		BlockType type(true, { 0.0f, 0.0f, 1.0f }, &slabShape);
+		type.fill = slab_fill;
+		blockType.Add(type);
+	}
+	{ // blue stair
+		BlockType type(true, { 0.0f, 0.0f, 1.0f }, &stairShape);
+		type.fill = stair_fill;
+		blockType.Add(type);
+	}
 
 	generate.Space(0);
 	generate.Solids({ 1, 4, 7, 10 });