charcoal/CharcoalBuiltin/PoseableBatch.h

#pragma once

#include <charcoal/Batch.h>
#include <charcoal/Renderable.h>
#include <charcoal/Poseable.h>
#include "BuiltinBatch.h"

namespace charcoal
{
	namespace builtin
	{
		// Note: If anything is changed in this file, it must also be changed in Poseable2DBatch
		template <typename VertexType, typename IndexType, int orientation_attrib_offset, typename RenderableT = RenderableT<VertexType, IndexType> >
		class PoseableBatch : public builtin::Batch<VertexType, IndexType, 1, RenderableT>
		{
		public:
			PoseableBatch(
				RenderableT* renderable,
				int element_count
			) : PoseableBatch(renderable, element_count, element_count)
			{}

			PoseableBatch(
				RenderableT* renderable,
				int element_count,
				int element_render_count
			) : builtin::Batch<VertexType, IndexType, 1, RenderableT>(renderable, element_render_count), m_orientation_elements(element_count)
			{}

			virtual ~PoseableBatch() {}

			void reset_rendered() { charcoal::Batch<VertexType, IndexType, 1, RenderableT>::m_element_render_count = 0; }

			void add_rendered(const Poseable& poseable) { m_orientation_elements[charcoal::Batch<VertexType, IndexType, 1, RenderableT>::m_element_render_count++] = poseable.get_orientation_matrix(); }

		protected:
			void setup_element_buffers()
			{
				glBindBuffer(GL_ARRAY_BUFFER, charcoal::Batch<VertexType, IndexType, 1, RenderableT>::m_element_buffers[0]);
				glBufferData(GL_ARRAY_BUFFER, m_orientation_elements.size() * sizeof(mat4), NULL, GL_STREAM_DRAW);
			}

			void update_element_buffers()
			{
				// TODO: There are probably better ways to do this. Should check with the old engine to see what I did there.
				glBindBuffer(GL_ARRAY_BUFFER, charcoal::Batch<VertexType, IndexType, 1, RenderableT>::m_element_buffers[0]);
				glBufferData(GL_ARRAY_BUFFER, m_orientation_elements.size() * sizeof(mat4), NULL, GL_STREAM_DRAW);
				glBufferSubData(GL_ARRAY_BUFFER, 0, m_orientation_elements.size() * sizeof(mat4), m_orientation_elements.data());
			}

			virtual void setup_vao_vertex() = 0;

			void setup_vao() override
			{
				setup_vao_vertex();

				glBindBuffer(GL_ARRAY_BUFFER, charcoal::Batch<VertexType, IndexType, 1, RenderableT>::m_element_buffers[0]);

				glEnableVertexAttribArray(orientation_attrib_offset + 0);
				glEnableVertexAttribArray(orientation_attrib_offset + 1);
				glEnableVertexAttribArray(orientation_attrib_offset + 2);
				glEnableVertexAttribArray(orientation_attrib_offset + 3);

				glVertexAttribPointer(orientation_attrib_offset + 0, 4, GL_FLOAT, GL_FALSE, sizeof(mat4), (void*)(0 * sizeof(mat4::col_type)));
				glVertexAttribPointer(orientation_attrib_offset + 1, 4, GL_FLOAT, GL_FALSE, sizeof(mat4), (void*)(1 * sizeof(mat4::col_type)));
				glVertexAttribPointer(orientation_attrib_offset + 2, 4, GL_FLOAT, GL_FALSE, sizeof(mat4), (void*)(2 * sizeof(mat4::col_type)));
				glVertexAttribPointer(orientation_attrib_offset + 3, 4, GL_FLOAT, GL_FALSE, sizeof(mat4), (void*)(3 * sizeof(mat4::col_type)));

				glVertexAttribDivisor(orientation_attrib_offset + 0, 1); // Send the orientation data for each instance drawn
				glVertexAttribDivisor(orientation_attrib_offset + 1, 1); // Send the orientation data for each instance drawn
				glVertexAttribDivisor(orientation_attrib_offset + 2, 1); // Send the orientation data for each instance drawn
				glVertexAttribDivisor(orientation_attrib_offset + 3, 1); // Send the orientation data for each instance drawn
			}

			std::vector<mat4> m_orientation_elements;
		};
	}
}