Add backends

- Renamed GfxOpenGL to GfxOPenGL2
- Added GfxOpenGL3 backend for OpenGL 3.3+
- Added WIP DirectX9 backend
- Added structure for Citro3D
- Added linear Allocator

backends/include/pd_system/ctr-linear-allocator.hpp

@@ -0,0 +1,67 @@
+#pragma once
+
+#ifdef __3DS__
+#include <3ds.h>
+#endif
+
+#include <limits>
+#include <memory>
+#include <stdexcept>
+
+// Custom C++ Allocator class to interface with libctru linear heap memory
+// based on this guide:
+// https://johnfarrier.com/custom-allocators-in-c-high-performance-memory-management/
+
+namespace PD {
+template <typename T>
+class LinearAllocator {
+ public:
+  using value_type = T;
+  LinearAllocator() noexcept = default;
+  template <typename U>
+  constexpr LinearAllocator(const LinearAllocator<U>&) noexcept {}
+
+  T* allocate(std::size_t n) {
+    if (n > max_size()) {
+      throw std::runtime_error("[PD] LinearAllocator: Bad alloc!");
+    }
+#ifdef __3DS__
+    return static_cast<T*>(linearAlloc(n * sizeof(T)));
+#else
+    return static_cast<T*>(malloc(n * sizeof(T)));
+#endif
+  }
+#ifdef __3DS__
+  void deallocate(T* p, std::size_t) noexcept { linearFree(p); }
+#else
+  void deallocate(T* p, std::size_t) noexcept { free(p); }
+#endif
+
+  template <class U, class... Args>
+  void construct(U* p, Args&&... args) {
+    ::new ((void*)p) U(std::forward<Args>(args)...);
+  }
+
+  template <class U>
+  void destroy(U* p) {
+    p->~U();
+  }
+
+  friend bool operator==(const LinearAllocator, const LinearAllocator) {
+    return true;
+  }
+  friend bool operator!=(const LinearAllocator, const LinearAllocator) {
+    return false;
+  }
+
+#ifdef __3DS__
+  // Use linearSpace free as max_size to not allocate out of bounds
+  // or to b eable to see a crash report screen.
+  size_t max_size() const noexcept { return linearSpaceFree(); }
+#else
+  size_t max_size() const noexcept {
+    return std::numeric_limits<size_t>::max();
+  }
+#endif
+};
+}  // namespace PD

backends/include/pd_system/gfx_citro3d.hpp

@@ -0,0 +1,38 @@
+#pragma once
+
+#include <pd/drivers/gfx.hpp>
+#include <pd_system/ctr-linear-allocator.hpp>
+
+namespace PD {
+struct GfxCitro3DConfig {
+  // Vertex Allocator
+  template <typename T>
+  using VertexAlloc = LinearAllocator<T>;
+  // Index Allocator
+  template <typename T>
+  using IndexAlloc = LinearAllocator<T>;
+
+  static constexpr size_t NumVertices = 32768;  // 8192*4
+  static constexpr size_t NumIndices = 49152;   // 8192*6
+};
+
+class GfxCitro3D : public GfxDriverBase<GfxCitro3DConfig> {
+ public:
+  GfxCitro3D() : GfxDriverBase("Citro3D") {}
+  ~GfxCitro3D() {}
+
+  void SysInit() override;
+  void SysDeinit() override;
+  void Submit(size_t count, size_t start) override;
+  void BindTexture(TextureID id) override;
+  void SysReset() override;
+  TextureID LoadTexture(const std::vector<PD::u8>& pixels, int w, int h,
+                        TextureFormat type = TextureFormat::RGBA32,
+                        TextureFilter filter = TextureFilter::Linear) override;
+  void DeleteTexture(const TextureID& tex) override;
+
+ private:
+  struct Impl;
+  Impl* impl = nullptr;
+};
+}  // namespace PD

backends/include/pd_system/gfx_directx9.hpp

@@ -0,0 +1,39 @@
+#pragma once
+
+#include <pd/drivers/gfx.hpp>
+
+namespace PD {
+struct GfxDirectX9Config {
+  // Vertex Allocator
+  template <typename T>
+  using VertexAlloc = std::allocator<T>;
+  // Index Allocator
+  template <typename T>
+  using IndexAlloc = std::allocator<T>;
+
+  static constexpr size_t NumVertices = 32768;  // 8192*4
+  static constexpr size_t NumIndices = 49152;   // 8192*6
+};
+
+class GfxDirectX9 : public GfxDriverBase<GfxDirectX9Config> {
+ public:
+  GfxDirectX9(void* device = nullptr)
+      : GfxDriverBase("DirectX9"), pDevice(device) {}
+  ~GfxDirectX9() {}
+
+  void SysInit() override;
+  void SysDeinit() override;
+  void Submit(size_t count, size_t start) override;
+  void BindTexture(TextureID id) override;
+  void SysReset() override;
+  TextureID LoadTexture(const std::vector<PD::u8>& pixels, int w, int h,
+                        TextureFormat type = TextureFormat::RGBA32,
+                        TextureFilter filter = TextureFilter::Linear) override;
+  void DeleteTexture(const TextureID& tex) override;
+
+ private:
+  struct Impl;
+  Impl* impl = nullptr;
+  void* pDevice = nullptr;
+};
+}  // namespace PD

backends/include/pd_system/gfx_opengl2.hpp

@@ -3,22 +3,22 @@
 #include <pd/drivers/gfx.hpp>
 
 namespace PD {
-struct GfxOpenGLConfig {
+struct GfxOpenGL2Config {
   // Vertex Allocator
   template <typename T>
   using VertexAlloc = std::allocator<T>;
   // Index Allocator
   template <typename T>
   using IndexAlloc = std::allocator<T>;
-  using IndexType = u32;  // Index Type
 
   static constexpr size_t NumVertices = 32768;  // 8192*4
   static constexpr size_t NumIndices = 49152;   // 8192*6
 };
-class GfxOpenGL : public GfxDriverBase<GfxOpenGLConfig> {
+
+class GfxOpenGL2 : public GfxDriverBase<GfxOpenGL2Config> {
  public:
-  GfxOpenGL(): GfxDriverBase("OpenGL2") {}
-  ~GfxOpenGL() {}
+  GfxOpenGL2() : GfxDriverBase("OpenGL2") {}
+  ~GfxOpenGL2() {}
 
   void SysInit() override;
   void SysDeinit() override;
@@ -38,5 +38,7 @@ class GfxOpenGL : public GfxDriverBase<GfxOpenGLConfig> {
   int pLocTex = 0;
   int pLocAlfa = 0;
   int pLocProjection = 0;
+  static const char* pVertCode;
+  static const char* pFragCode;
 };
 }  // namespace PD

backends/include/pd_system/gfx_opengl3.hpp

@@ -0,0 +1,44 @@
+#pragma once
+
+#include <pd/drivers/gfx.hpp>
+
+namespace PD {
+struct GfxOpenGL3Config {
+  // Vertex Allocator
+  template <typename T>
+  using VertexAlloc = std::allocator<T>;
+  // Index Allocator
+  template <typename T>
+  using IndexAlloc = std::allocator<T>;
+
+  static constexpr size_t NumVertices = 32768;  // 8192*4
+  static constexpr size_t NumIndices = 49152;   // 8192*6
+};
+
+class GfxOpenGL3 : public GfxDriverBase<GfxOpenGL3Config> {
+ public:
+  GfxOpenGL3() : GfxDriverBase("OpenGL3") {}
+  ~GfxOpenGL3() {}
+
+  void SysInit() override;
+  void SysDeinit() override;
+  void Submit(size_t count, size_t start) override;
+  void BindTexture(TextureID id) override;
+  void SysReset() override;
+  TextureID LoadTexture(const std::vector<PD::u8>& pixels, int w, int h,
+                        TextureFormat type = TextureFormat::RGBA32,
+                        TextureFilter filter = TextureFilter::Linear) override;
+  void DeleteTexture(const TextureID& tex) override;
+
+ private:
+  u32 pShader = 0;
+  u32 VBO = 0;
+  u32 IBO = 0;
+  u32 VAO = 0;
+  int pLocTex = 0;
+  int pLocAlfa = 0;
+  int pLocProjection = 0;
+  static const char* pVertCode;
+  static const char* pFragCode;
+};
+}  // namespace PD

backends/include/pd_system/gl-helper.hpp

@@ -0,0 +1,7 @@
+#pragma once
+
+#include <pd/common.hpp>
+
+namespace PD {
+u32 CreateShaderProgram(const char* vert, const char* frag);
+}

backends/include/pdsystem

@@ -0,0 +1,6 @@
+#pragma once
+
+#include <pd_system/gfx_citro3d.hpp>
+#include <pd_system/gfx_directx9.hpp>
+#include <pd_system/gfx_opengl2.hpp>
+#include <pd_system/gfx_opengl3.hpp>