feat: frame exporting

3 files changed, 91 insertions, 0 deletions

diff --git a/src/rendering/framebuffer.cpp b/src/rendering/framebuffer.cpp
new file mode 100644
index 0000000..e227dcf
--- /dev/null
+++ b/src/rendering/framebuffer.cpp
@@ -0,0 +1,17 @@
+#include "framebuffer.h"
+#include "renderer.h"
+
+#include "platform/opengl/opengl_framebuffer.h"
+
+namespace Donut
+{
+    Ref<Framebuffer> Framebuffer::create(const FramebufferSpecification& spec)
+    {
+        switch (Renderer::get_api())
+        {
+            case RendererAPI::API::OpenGL:  return create_ref<OpenGLFramebuffer>(spec);
+        }
+
+        return nullptr;
+    }
+};
diff --git a/src/rendering/framebuffer.h b/src/rendering/framebuffer.h
new file mode 100644
index 0000000..1d42d85
--- /dev/null
+++ b/src/rendering/framebuffer.h
@@ -0,0 +1,65 @@
+#pragma once
+
+#include "core/memory.h"
+#include "texture.h"
+
+namespace Donut
+{
+    enum class FramebufferTextureFormat
+    {
+        None = 0,
+        
+        RGBA8,
+        RED_INTEGER,
+        
+        DEPTH24STENCIL8,
+        
+        Depth = DEPTH24STENCIL8
+    };
+
+    struct FramebufferTextureSpecification
+    {
+        FramebufferTextureSpecification() = default;
+        FramebufferTextureSpecification(FramebufferTextureFormat format)
+            : texture_format(format) {}
+
+        FramebufferTextureFormat texture_format = FramebufferTextureFormat::None;
+    };
+
+    struct FramebufferAttachmentSpecification
+    {
+        FramebufferAttachmentSpecification() = default;
+        FramebufferAttachmentSpecification(std::initializer_list<FramebufferTextureSpecification> attachments)
+            : attachments(attachments) {}
+
+        std::vector<FramebufferTextureSpecification> attachments;
+    };
+
+    struct FramebufferSpecification
+    {
+        uint32_t Width = 0, Height = 0;
+        FramebufferAttachmentSpecification attachments;
+        uint32_t Samples = 1;
+
+        bool SwapChainTarget = false;
+    };
+
+    class Framebuffer
+    {
+    public:
+        virtual ~Framebuffer() = default;
+
+        virtual void bind()   = 0;
+        virtual void unbind() = 0;
+
+        virtual void resize(uint32_t width, uint32_t height)           = 0;
+        virtual int  read_pixel(uint32_t attachment_index, int x, int y) = 0;
+
+        virtual void clear_attachment(uint32_t attachment_index, int value)       = 0;
+        virtual uint32_t get_color_attachment_renderer_id(uint32_t index = 0) const = 0;
+
+        virtual const FramebufferSpecification& get_specification() const = 0;
+
+        static Ref<Framebuffer> create(const FramebufferSpecification& spec);
+    };
+};
diff --git a/src/rendering/renderer.h b/src/rendering/renderer.h
index 67ad998..ea200db 100644
--- a/src/rendering/renderer.h
+++ b/src/rendering/renderer.h
@@ -3,6 +3,7 @@
 #include "core/memory.h"
 #include "vertex_array.h"
 #include "shader.h"
+#include "framebuffer.h"
 
 #include <glm/glm.hpp>
 
@@ -41,6 +42,8 @@ namespace Donut
         virtual void bind_image_texture(uint32_t texture_id, 
                                       uint32_t slot = 0, 
                                       bool read_only = false)              = 0;
+        virtual void read_pixels(uint32_t x, uint32_t y, uint32_t width, uint32_t height, 
+                                uint32_t format, uint32_t type, void* pixels) = 0;
 
         inline static API get_api()         { return s_api; }
         inline static void set_api(API api) { s_api = api;  }
@@ -122,6 +125,12 @@ namespace Donut
             s_renderer_api->bind_image_texture(texture_id, slot, read_only);
         }
 
+        inline static void read_pixels(uint32_t x, uint32_t y, uint32_t width, uint32_t height, 
+                                      uint32_t format, uint32_t type, void* pixels)
+        {
+            s_renderer_api->read_pixels(x, y, width, height, format, type, pixels);
+        }
+
     private:
         static Scope<RendererAPI> s_renderer_api;
     };