From 44bdc63c6f3ffe2c50f35a2b1be81364e2d07963 Mon Sep 17 00:00:00 2001
From: Marc Gilleron <marc.gilleron@gmail.com>
Date: Fri, 28 Sep 2018 01:11:28 +0100
Subject: [PATCH] Added an image-based terrain generator for testing (ported
 from the GDScript demo)

---
 register_types.cpp       |  2 +
 voxel_provider.cpp       |  5 ++-
 voxel_provider_image.cpp | 79 ++++++++++++++++++++++++++++++++++++++++
 voxel_provider_image.h   | 29 +++++++++++++++
 4 files changed, 113 insertions(+), 2 deletions(-)
 create mode 100644 voxel_provider_image.cpp
 create mode 100644 voxel_provider_image.h

diff --git a/register_types.cpp b/register_types.cpp
index 0f7ccf3..95a68ad 100644
--- a/register_types.cpp
+++ b/register_types.cpp
@@ -5,6 +5,7 @@
 #include "voxel_map.h"
 #include "voxel_terrain.h"
 #include "voxel_provider_test.h"
+#include "voxel_provider_image.h"
 #include "voxel_mesher_smooth.h"
 
 void register_voxel_types() {
@@ -17,6 +18,7 @@ void register_voxel_types() {
 	ClassDB::register_class<VoxelTerrain>();
 	ClassDB::register_class<VoxelProvider>();
 	ClassDB::register_class<VoxelProviderTest>();
+	ClassDB::register_class<VoxelProviderImage>();
 	ClassDB::register_class<VoxelMesherSmooth>();
 
 }
diff --git a/voxel_provider.cpp b/voxel_provider.cpp
index 5db8333..4f34b08 100644
--- a/voxel_provider.cpp
+++ b/voxel_provider.cpp
@@ -36,7 +36,8 @@ void VoxelProvider::_immerge_block(Ref<VoxelBuffer> buffer, Vector3 origin_in_vo
 }
 
 void VoxelProvider::_bind_methods() {
+	// Note: C++ inheriting classes don't need to re-bind these, because they are bindings that call the actual virtual methods
 
-	ClassDB::bind_method(D_METHOD("emerge_block", "out_buffer", "block_pos"), &VoxelProvider::_emerge_block);
-	ClassDB::bind_method(D_METHOD("immerge_block", "buffer", "block_pos"), &VoxelProvider::_immerge_block);
+	ClassDB::bind_method(D_METHOD("emerge_block", "out_buffer", "origin_in_voxels"), &VoxelProvider::_emerge_block);
+	ClassDB::bind_method(D_METHOD("immerge_block", "buffer", "origin_in_voxels"), &VoxelProvider::_immerge_block);
 }
diff --git a/voxel_provider_image.cpp b/voxel_provider_image.cpp
new file mode 100644
index 0000000..380c931
--- /dev/null
+++ b/voxel_provider_image.cpp
@@ -0,0 +1,79 @@
+#include "voxel_provider_image.h"
+
+VoxelProviderImage::VoxelProviderImage(): _channel(0) {
+}
+
+void VoxelProviderImage::set_image(Ref<Image> im) {
+	_image = im;
+}
+
+Ref<Image> VoxelProviderImage::get_image() const {
+	return _image;
+}
+
+void VoxelProviderImage::set_channel(int channel) {
+	_channel = channel;
+}
+
+int VoxelProviderImage::get_channel() const {
+	return _channel;
+}
+
+void VoxelProviderImage::emerge_block(Ref<VoxelBuffer> p_out_buffer, Vector3i origin_in_voxels) {
+
+	int ox = origin_in_voxels.x;
+	int oy = origin_in_voxels.y;
+	int oz = origin_in_voxels.z;
+
+	Image &image = **_image;
+	VoxelBuffer &out_buffer = **p_out_buffer;
+
+	image.lock();
+
+	int im_w = image.get_width();
+	int im_h = image.get_height();
+	int im_wm = im_w - 1;
+	int im_hm = im_h - 1;
+
+	int x = 0;
+	int z = 0;
+
+	int bs = out_buffer.get_size().x;
+
+	int dirt = 1;
+
+	while (z < bs) {
+		while (x < bs) {
+
+			Color c = image.get_pixel((ox + x) & im_wm, (oz + z) & im_hm);
+			int h = int(c.r * 200.0) - 50;
+			h -= oy;
+			if (h > 0) {
+				if (h > bs) {
+					h = bs;
+				}
+				out_buffer.fill_area(dirt, Vector3(x, 0, z), Vector3(x + 1, h, z + 1), _channel);
+			}
+
+			x += 1;
+		}
+		z += 1;
+		x = 0;
+	}
+
+	image.unlock();
+}
+
+void VoxelProviderImage::_bind_methods() {
+
+	ClassDB::bind_method(D_METHOD("set_image", "image"), &VoxelProviderImage::set_image);
+	ClassDB::bind_method(D_METHOD("get_image"), &VoxelProviderImage::get_image);
+
+	ClassDB::bind_method(D_METHOD("set_channel", "channel"), &VoxelProviderImage::set_channel);
+	ClassDB::bind_method(D_METHOD("get_channel"), &VoxelProviderImage::get_channel);
+
+	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "image", PROPERTY_HINT_RESOURCE_TYPE, "Image"), "set_image", "get_image");
+	ADD_PROPERTY(PropertyInfo(Variant::INT, "channel"), "set_channel", "get_channel");
+}
+
+
diff --git a/voxel_provider_image.h b/voxel_provider_image.h
new file mode 100644
index 0000000..2393cb6
--- /dev/null
+++ b/voxel_provider_image.h
@@ -0,0 +1,29 @@
+#ifndef HEADER_VOXEL_PROVIDER_IMAGE
+#define HEADER_VOXEL_PROVIDER_IMAGE
+
+#include "voxel_provider.h"
+#include <core/image.h>
+
+// Provides infinite tiling heightmap based on an image
+class VoxelProviderImage : public VoxelProvider {
+	GDCLASS(VoxelProviderImage, VoxelProvider)
+public:
+	VoxelProviderImage();
+
+	void set_image(Ref<Image> im);
+	Ref<Image> get_image() const;
+
+	void set_channel(int channel);
+	int get_channel() const;
+
+	void emerge_block(Ref<VoxelBuffer> p_out_buffer, Vector3i origin_in_voxels);
+
+private:
+	static void _bind_methods();
+
+private:
+	Ref<Image> _image;
+	int _channel;
+};
+
+#endif // HEADER_VOXEL_PROVIDER_IMAGE