Question

我正在为游戏制作一种ascii画布。我认为在cp437样式中使用ascii字形的spritesheet来绘制ascii艺术会更有效率。我需要一种方法来为字形的背景和前景着色，以便我使用片段着色器。使用着色器将我降至7 fps。不使用着色器，我得到大约131.

我做错了什么吗？循环遍历字符串向量（以及字符串中的每个字符）是否过于昂贵，计算表单上字形的位置，设置纹理位置，然后使用着色器为每个字符绘制精灵？

int main() {
    sf::RenderWindow rt(sf::VideoMode(1280, 720), "Demo Game");

    sf::Texture texture;
    texture.loadFromFile("Resources/courier_8x16.png");
    texture.setSmooth(false);
    sf::Sprite sprite(texture);
    sf::Shader shader;
    shader.loadFromFile("cycle.frag", sf::Shader::Fragment);
    shader.setUniform("texture", sf::Shader::CurrentTexture);

    sf::Clock clock;
    sf::Time timeSinceLastUpdate = sf::Time::Zero;

    std::vector<std::string> chars = std::vector<std::string>(50, std::string(100, 'X'));
    while (rt.isOpen())
    {
        processEvents();
        timeSinceLastUpdate += clock.restart();

        while (timeSinceLastUpdate > TimePerFrame)
        {
            timeSinceLastUpdate -= TimePerFrame;
            processEvents();
            update(TimePerFrame);
        }

        //render();
        rt.clear();

        for (int y = 0; y < chars.size(); y++)
        {
            for (int x = 0; x < chars[y].size(); x++)
            {
                //bg and fg colors will be in a 2D vector and used here
                shader.setUniform("foreground", sf::Glsl::Vec4(std::Color.White));
                shader.setUniform("background", sf::Glsl::Vec4(std::Color.Black));

                //uses decimal value of char and dimensions
                //to find location of appropriate glyph in sprite sheet
                sprite.setTextureRect(sf::IntRect((chars[y][x] % 16) * 8, (chars[y][x] / 16) * 16, 8, 16));
                sprite.setPosition(x * 8, y * 16);

                rt.draw(sprite, &shader);
            }

        }

        rt.display();

    }


}

这是着色器代码：

//////cycle.frag
uniform vec4 foreground;
uniform vec4 background;
uniform sampler2D texture;

void main()
{
    vec4 pixel = texture2D(texture, gl_TexCoord[0].xy);
    if (pixel.r < .1)
        pixel = background;
    else
        pixel = foreground;

    gl_FragColor = pixel;
}

这里是精灵表:(所有段落符号只是占位符）

如何在c ++ / sfml中更有效地使用着色器？

0 个答案: