Cet article appartient à une série de tutoriels dédiés à SFML. Le lecteur est invité à se référer aux autres sections de ce tutoriel en suivant ce lien : SFML tutoriel.
Cette page explique comment afficher un shader "effet eau" avec SFML. L'exemple présenté sur cette page a été réalisé avec les versions suivantes :
Cette vidéo vous donne un aperçu du résultat :
Cet exemple montre comment créer un shaders "effet eau" en SFML.
/*!
* \file main.cpp
* \brief apply a heat shader to a sprite (http://www.lucidarme.me/?p=6127)
* \author Philippe Lucidarme (from https://github.com/SFML/SFML/wiki/Source:-HeatHazeShader)
* \version 1.0
* \date 12/19/2016
*/
// SFML libraries
#include <SFML/Graphics.hpp>
#include <iostream>
#include <math.h>
int main()
{
// _____________________
// ::: Create window :::
// Create a window with the same pixel depth as the desktop
sf::VideoMode desktopMode = sf::VideoMode::getDesktopMode();
sf::RenderWindow window(sf::VideoMode( desktopMode.width,
desktopMode.height,
desktopMode.bitsPerPixel),
"SFML part 5",
sf::Style::Fullscreen);
// Enable vertical sync. (vsync)
window.setVerticalSyncEnabled (true);
// ____________________
// ::: Load texture :::
// Create texture from PNG file
sf::Texture texture;
if (!texture.loadFromFile("../sfml-icon-small.png"))
{
std::cerr << "Error while loading texture" << std::endl;
return -1;
}
// Enable the smooth filter. The texture appears smoother so that pixels are less noticeable.
texture.setSmooth(true);
// _______________________________________
// ::: Create sprite and apply texture :::
// Create the sprite and apply the texture
sf::Sprite sprite;
sprite.setTexture(texture);
sf::FloatRect spriteSize=sprite.getGlobalBounds();
// Set origin in the middle of the sprite
sprite.setOrigin(spriteSize.width/2.,spriteSize.height/2.);
// _______________
// ::: Shaders :::
// Check if shaders are available
if (!sf::Shader::isAvailable())
{
std::cerr << "Shader are not available" << std::endl;
return -1;
}
// Load shaders
sf::Shader shader;
if (!shader.loadFromFile("../water.frag", sf::Shader::Fragment))
{
std::cerr << "Error while shaders" << std::endl;
return -1;
}
// ___________________________
// ::: Load distortion map :::
sf::Texture distortionMap;
if (!distortionMap.loadFromFile("../noiseWater.png"))
{
sf::err() << "Error while loading distortion map" << std::endl;
return -1;
}
// It is important to set repeated to true to enable scrolling upwards
distortionMap.setRepeated(true);
// Setting smooth to true lets us use small maps even on larger images
distortionMap.setSmooth(true);
// Set texture to the shader
shader.setParameter("currentTexture", sf::Shader::CurrentTexture);
shader.setParameter("distortionMapTexture", distortionMap);
// Shader parameters
float level = .5f;
// _________________
// ::: Main loop :::
sf::Clock timer;
while (window.isOpen())
{
// Process events
sf::Event event;
while (window.pollEvent(event))
{
// Close the window if a key is pressed or if requested
if (event.type == sf::Event::Closed) window.close();
// If a key is pressed
if (event.type == sf::Event::KeyPressed)
{
switch (event.key.code)
{
// If escape is pressed, close the application
case sf::Keyboard::Escape : window.close(); break;
// Process the up, down, left and right keys to modify parameters
case sf::Keyboard::Up : level -= .005f; break;
case sf::Keyboard::Down: level += .005f; break;
default : break;
}
}
}
if (level>0.8) level=0.8;
if (level<0.2) level=0.2;
// Set shader parameters
shader.setParameter("time", timer.getElapsedTime().asSeconds());
shader.setParameter("level",level);
// Clear the window and apply grey background
window.clear( sf::Color(127,127,127));
// Draw the sprite and apply shader
sprite.setPosition(window.getSize().x/2.,window.getSize().y/2.);
sprite.setScale(2,2);
window.draw(sprite,&shader);
// Update display and wait for vsync
window.display();
}
return 0;
}
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