celestia/src/celengine/pointstarvertexbuffer.h

78 lines
2.1 KiB
C++

// pointstarvertexbuffer.h
//
// Copyright (C) 2001-2019, the Celestia Development Team
// Original version by Chris Laurel <claurel@gmail.com>
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
#pragma once
#include <Eigen/Core>
#include "glshader.h"
class Color;
class Renderer;
class Texture;
// PointStarVertexBuffer is used when hardware supports point sprites.
class PointStarVertexBuffer
{
public:
using capacity_t = unsigned int;
PointStarVertexBuffer(const Renderer& _renderer, unsigned int _capacity);
~PointStarVertexBuffer();
PointStarVertexBuffer() = delete;
PointStarVertexBuffer(const PointStarVertexBuffer&) = delete;
PointStarVertexBuffer(PointStarVertexBuffer&&) = delete;
PointStarVertexBuffer& operator=(const PointStarVertexBuffer&) = delete;
PointStarVertexBuffer& operator=(PointStarVertexBuffer&&) = delete;
void startPoints();
void startSprites();
void render();
void finish();
inline void addStar(const Eigen::Vector3f& pos, const Color&, float);
void setTexture(Texture* /*_texture*/);
private:
struct StarVertex
{
Eigen::Vector3f position;
float size;
unsigned char color[4];
float pad;
};
const Renderer& renderer;
capacity_t capacity;
capacity_t nStars { 0 };
StarVertex* vertices { nullptr };
Texture* texture { nullptr };
bool useSprites { false };
IntegerShaderParameter starTexParam;
};
inline void PointStarVertexBuffer::addStar(const Eigen::Vector3f& pos,
const Color& color,
float size)
{
if (nStars < capacity)
{
vertices[nStars].position = pos;
vertices[nStars].size = size;
color.get(vertices[nStars].color);
nStars++;
}
if (nStars == capacity)
{
render();
nStars = 0;
}
}