fs2open.github.com/code/scpui/RocketRenderingInterface.h

#pragma once
//
//

#include "globalincs/pstypes.h"

#include "graphics/2d.h"
#include "graphics/generic.h"

// Our Assert conflicts with the definitions inside libRocket
#pragma push_macro("Assert")
#undef Assert

#include <Rocket/Core/RenderInterface.h>

#pragma pop_macro("Assert")

namespace scpui {

class RocketRenderingInterface : public Rocket::Core::RenderInterface {
	struct Texture {
		bool is_animation = false;

		generic_anim animation;

		int bm_handle = -1;

		std::unique_ptr<uint8_t[]> data;
	};

	struct CompiledGeometry {
		gr_buffer_handle vertex_buffer;
		gr_buffer_handle index_buffer;
		int num_elements = -1;

		Texture* texture = nullptr;
	};

	bool clipping_active = false;

	vec2d renderOffset;

	static Texture* get_texture(Rocket::Core::TextureHandle handle);

	static Rocket::Core::TextureHandle get_texture_handle(Texture* bitmap);

	void renderGeometry(gr_buffer_handle vertex_buffer,
		gr_buffer_handle index_buffer,
		int num_elements,
		int bitmap,
		const Rocket::Core::Vector2f& translation);

	gr_buffer_handle vertex_stream_buffer;
	gr_buffer_handle index_stream_buffer;

	vertex_layout layout;

	float horizontal_swipe_offset = std::numeric_limits<float>::infinity();

  public:
	RocketRenderingInterface();
	~RocketRenderingInterface() override;

	/**
	 * @brief Renders geometry from a memory buffer
	 *
	 * @details This uses an internal streaming buffer for storing the data. This is not as fast as using compiled
	 * geometry but needs to be supported for the debugger.
	 *
	 * @param vertices
	 * @param num_vertices
	 * @param indices
	 * @param num_indices
	 * @param texture
	 * @param translation
	 */
	void RenderGeometry(Rocket::Core::Vertex* vertices, int num_vertices, int* indices, int num_indices,
	                    Rocket::Core::TextureHandle texture, const Rocket::Core::Vector2f& translation) override;

	/**
	 * @brief Compiles geometry to a GPU buffer
	 *
	 * @details This uses GPU buffers provided by the graphics interface and stores the data in them. The buffers are
	 * allocated as static so rendering them should be pretty fast.
	 *
	 * @param vertices
	 * @param num_vertices
	 * @param indices
	 * @param num_indices
	 * @param texture
	 * @return
	 */
	Rocket::Core::CompiledGeometryHandle CompileGeometry(Rocket::Core::Vertex* vertices, int num_vertices, int* indices,
	                                                     int num_indices, Rocket::Core::TextureHandle texture) override;

	/**
	 * @brief Renders compiled geometry
	 *
	 * @details Takes the geometry buffers in the specified handle and renders them with the specified translation.
	 *
	 * @param geometry
	 * @param translation
	 */
	void RenderCompiledGeometry(Rocket::Core::CompiledGeometryHandle geometry,
	                            const Rocket::Core::Vector2f& translation) override;

	/**
	 * @brief Releases the geometry buffers
	 *
	 * @details Frees the underlying geometry buffers.
	 *
	 * @param geometry
	 */
	void ReleaseCompiledGeometry(Rocket::Core::CompiledGeometryHandle geometry) override;

	void EnableScissorRegion(bool enable) override;

	void SetScissorRegion(int x, int y, int width, int height) override;

	bool LoadTexture(Rocket::Core::TextureHandle& texture_handle, Rocket::Core::Vector2i& texture_dimensions,
	                 const Rocket::Core::String& source) override;

	bool GenerateTexture(Rocket::Core::TextureHandle& texture_handle, const Rocket::Core::byte* source,
	                     const Rocket::Core::Vector2i& source_dimensions) override;

	void ReleaseTexture(Rocket::Core::TextureHandle texture) override;

	/**
	 * @brief Sets the render offset of future drawing operations
	 *
	 * @details This allows to offset any subsequent rendering operations without changing the libRocket markup.
	 *
	 * @param render_offset
	 */
	void setRenderOffset(const vec2d& render_offset);

	float GetPixelsPerInch() override;

	/**
	 * @brief Set the horizontal swipe value for the following render operations
	 * @param value The pixel location where the swipe is. Set to infinity to disable.
	 */
	void setHorizontalSwipeOffset(float value);

	/**
	 * @brief From a texture handle, get the bitmap number for bmpman
	 * @param handle The libRocket texture handle
	 * @return The bitmap number
	 */
	static int getBitmapNum(Rocket::Core::TextureHandle handle);

	/**
	 * @brief Advances an animation by the specified amount of seconds
	 * @param handle The libRocket texture handle to modify
	 * @param advanceTime The time to advance the animation by
	 */
	static void advanceAnimation(Rocket::Core::TextureHandle handle, float advanceTime);
};

} // namespace scpui