使用Kenny Mitchell在GPU Gems 3中提供的GLSL着色器源代码,我尝试使用SFML 2.0创建一些2D神射线。当前,每当我编译和调试项目时,蒙版纹理和精灵(分别为“image.png”和“sprite”)就会完全消失。我目前设置的项目非常粗糙,仅包含一个main.cpp文件和着色器文件,尽管我感觉我需要的资源比目前的要多。任何帮助将非常感激!源代码将在下面提供。
main.cpp:
#include <SFML\Graphics.hpp>
#include <SFML\System.hpp>
#include <SFML\Window.hpp>
#include <iostream>
void main()
{
sf::RenderWindow _window(sf::VideoMode(800, 480, 32), "Lighting Test");
_window.setFramerateLimit(60);
sf::Shader lightingShader;
sf::RenderStates renderState;
sf::Texture texture;
texture.loadFromFile("image.png");
sf::Sprite sprite;
sprite.setTexture(texture);
sf::Texture backgroundTexture;
backgroundTexture.loadFromFile("light.png");
sf::Sprite background;
background.setTexture(backgroundTexture);
while (_window.isOpen())
{
int x = sf::Mouse::getPosition(_window).x;
int y = sf::Mouse::getPosition(_window).y;
lightingShader.loadFromFile("lightingShader.vert", "lightingShader.frag");
lightingShader.setParameter("exposure", 0.25f);
lightingShader.setParameter("decay", 0.97f);
lightingShader.setParameter("density", 0.97f);
lightingShader.setParameter("weight", 0.5f);
lightingShader.setParameter("lightPositionOnScreen", sf::Vector2f(0.5f, 0.5f));
lightingShader.setParameter("myTexture", sf::Shader::CurrentTexture);
renderState.shader = &lightingShader;
_window.clear(sf::Color::Black);
sprite.setPosition(x, y);
//sprite.setColor(sf::Color::Black);
//background.setPosition(400, 240);
_window.draw(background);
_window.draw(sprite, renderState);
_window.display();
}
}
lightingShader.vert:
void main()
{
gl_TexCoord[0] = gl_MultiTexCoord0;
gl_Position = ftransform();
}
lightingShader.frag:
uniform float exposure;
uniform float decay;
uniform float density;
uniform float weight;
uniform vec2 lightPositionOnScreen;
uniform sampler2D myTexture;
const int NUM_SAMPLES = 100 ;
void main()
{
vec2 deltaTextCoord = vec2( gl_TexCoord[0].st - lightPositionOnScreen.xy );
vec2 textCoord = gl_TexCoord[0].st;
deltaTextCoord *= 1.0 / float(NUM_SAMPLES) * density;
float illuminationDecay = 1.0;
for(int i=0; i < NUM_SAMPLES ; i++)
{
textCoord -= deltaTextCoord;
vec4 sample = texture2D(myTexture, textCoord);
sample *= illuminationDecay * weight;
gl_FragColor += sample;
illuminationDecay *= decay;
}
gl_FragColor *= exposure;
}
最佳答案
我终于自己解决了这个问题。原来我创建的顶点着色器是不必要的,而我要做的就是替换:lightingShader.loadFromFile("lightingShader.vert", "lightingShader.frag");
带有:lightingShader.loadFromFile("lightingShader.frag", sf::Shader::Type::Fragment);
。