Fix the material preview sphere

Author: BlueCube3310

editor/inspector/editor_preview_plugins.cpp

@@ -393,7 +393,7 @@ EditorMaterialPreviewPlugin::EditorMaterialPreviewPlugin() {
 
 	int lats = 32;
 	int lons = 32;
-	const double lat_step = Math::TAU / lats;
+	const double lat_step = Math::PI / lats;
 	const double lon_step = Math::TAU / lons;
 	real_t radius = 1.0;
 
@@ -428,22 +428,27 @@ EditorMaterialPreviewPlugin::EditorMaterialPreviewPlugin() {
 				Vector3(x0 * zr0, z0, y0 * zr0)
 			};
 
-#define ADD_POINT(m_idx)                                                                       \
-	normals.push_back(v[m_idx]);                                                               \
-	vertices.push_back(v[m_idx] * radius);                                                     \
-	{                                                                                          \
-		Vector2 uv(Math::atan2(v[m_idx].x, v[m_idx].z), Math::atan2(-v[m_idx].y, v[m_idx].z)); \
-		uv /= Math::PI;                                                                        \
-		uv *= 4.0;                                                                             \
-		uv = uv * 0.5 + Vector2(0.5, 0.5);                                                     \
-		uvs.push_back(uv);                                                                     \
-	}                                                                                          \
-	{                                                                                          \
-		Vector3 t = tt.xform(v[m_idx]);                                                        \
-		tangents.push_back(t.x);                                                               \
-		tangents.push_back(t.y);                                                               \
-		tangents.push_back(t.z);                                                               \
-		tangents.push_back(1.0);                                                               \
+#define ADD_POINT(m_idx)                                                                               \
+	normals.push_back(v[m_idx]);                                                                       \
+	vertices.push_back(v[m_idx] * radius);                                                             \
+	{                                                                                                  \
+		Vector2 uv;                                                                                    \
+		if (j >= lons / 2) {                                                                           \
+			uv = Vector2(Math::atan2(-v[m_idx].x, -v[m_idx].z), Math::atan2(v[m_idx].y, -v[m_idx].z)); \
+		} else {                                                                                       \
+			uv = Vector2(Math::atan2(v[m_idx].x, v[m_idx].z), Math::atan2(-v[m_idx].y, v[m_idx].z));   \
+		}                                                                                              \
+		uv /= Math::PI;                                                                                \
+		uv *= 4.0;                                                                                     \
+		uv = uv * 0.5 + Vector2(0.5, 0.5);                                                             \
+		uvs.push_back(uv);                                                                             \
+	}                                                                                                  \
+	{                                                                                                  \
+		Vector3 t = tt.xform(v[m_idx]);                                                                \
+		tangents.push_back(t.x);                                                                       \
+		tangents.push_back(t.y);                                                                       \
+		tangents.push_back(t.z);                                                                       \
+		tangents.push_back(1.0);                                                                       \
 	}
 
 			ADD_POINT(0);