Reorganize source files into logical subdirectories

Co-authored-by: Hirek193 <23196899+Hirek193@users.noreply.github.com>

rendering/openglparticles.h

@@ -0,0 +1,51 @@
+/*
+This Source Code Form is subject to the
+terms of the Mozilla Public License, v.
+2.0. If a copy of the MPL was not
+distributed with this file, You can
+obtain one at
+http://mozilla.org/MPL/2.0/.
+*/
+
+#pragma once
+
+class opengl_camera;
+
+// particle data visualizer
+class opengl_particles {
+public:
+// constructors
+    opengl_particles() = default;
+// destructor
+    ~opengl_particles() {
+        if( m_buffer != -1 ) {
+            ::glDeleteBuffers( 1, &m_buffer ); } }
+// methods
+    void
+        update( opengl_camera const &Camera );
+    std::size_t
+        render( GLint const Textureunit );
+private:
+// types
+    struct particle_vertex {
+        glm::vec3 position; // 3d space
+        std::uint8_t color[ 4 ]; // rgba, unsigned byte format
+        glm::vec2 texture; // uv space
+        float padding[ 2 ]; // experimental, some gfx hardware allegedly works better with 32-bit aligned data blocks
+    };
+/*
+    using sourcedistance_pair = std::pair<smoke_source *, float>;
+    using source_sequence = std::vector<sourcedistance_pair>;
+*/
+    using particlevertex_sequence = std::vector<particle_vertex>;
+// methods
+// members
+/*
+    source_sequence m_sources; // list of particle sources visible in current render pass, with their respective distances to the camera
+*/
+    particlevertex_sequence m_particlevertices; // geometry data of visible particles, generated on the cpu end
+    GLuint m_buffer{ (GLuint)-1 }; // id of the buffer holding geometry data on the opengl end
+    std::size_t m_buffercapacity{ 0 }; // total capacity of the last established buffer
+};
+
+//---------------------------------------------------------------------------