SFML/examples/shader/Shader.cpp
Chris Thrasher 5735fd09d9
Rewrite sf::Event API to improve type safety
This new API is built on top of std::variant. This allows us to
store many different event types in a space-efficient way and access
the active event type in a type-safe manner that eliminates the
categories of UB that are possible with unions.

Co-authored-by: kimci86 <kimci86@hotmail.fr>
2023-11-09 00:19:38 -07:00

458 lines
15 KiB
C++

////////////////////////////////////////////////////////////
// Headers
////////////////////////////////////////////////////////////
#include "Effect.hpp"
#include <array>
#include <random>
namespace
{
std::random_device rd;
std::mt19937 rng(rd());
} // namespace
const sf::Font* Effect::s_font = nullptr;
////////////////////////////////////////////////////////////
// "Pixelate" fragment shader
////////////////////////////////////////////////////////////
class Pixelate : public Effect
{
public:
Pixelate() : Effect("Pixelate")
{
}
bool onLoad() override
{
// Load the texture and initialize the sprite
if (!m_texture.loadFromFile("resources/background.jpg"))
return false;
m_sprite.emplace(m_texture);
// Load the shader
if (!m_shader.loadFromFile("resources/pixelate.frag", sf::Shader::Fragment))
return false;
m_shader.setUniform("texture", sf::Shader::CurrentTexture);
return true;
}
void onUpdate(float, float x, float y) override
{
m_shader.setUniform("pixel_threshold", (x + y) / 30);
}
void onDraw(sf::RenderTarget& target, const sf::RenderStates& states) const override
{
sf::RenderStates statesCopy(states);
statesCopy.shader = &m_shader;
target.draw(*m_sprite, statesCopy);
}
private:
sf::Texture m_texture;
std::optional<sf::Sprite> m_sprite;
sf::Shader m_shader;
};
////////////////////////////////////////////////////////////
// "Wave" vertex shader + "blur" fragment shader
////////////////////////////////////////////////////////////
class WaveBlur : public Effect
{
public:
WaveBlur() : Effect("Wave + Blur"), m_text(getFont())
{
}
bool onLoad() override
{
// Create the text
m_text.setString(
"Praesent suscipit augue in velit pulvinar hendrerit varius purus aliquam.\n"
"Mauris mi odio, bibendum quis fringilla a, laoreet vel orci. Proin vitae vulputate tortor.\n"
"Praesent cursus ultrices justo, ut feugiat ante vehicula quis.\n"
"Donec fringilla scelerisque mauris et viverra.\n"
"Maecenas adipiscing ornare scelerisque. Nullam at libero elit.\n"
"Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas.\n"
"Nullam leo urna, tincidunt id semper eget, ultricies sed mi.\n"
"Morbi mauris massa, commodo id dignissim vel, lobortis et elit.\n"
"Fusce vel libero sed neque scelerisque venenatis.\n"
"Integer mattis tincidunt quam vitae iaculis.\n"
"Vivamus fringilla sem non velit venenatis fermentum.\n"
"Vivamus varius tincidunt nisi id vehicula.\n"
"Integer ullamcorper, enim vitae euismod rutrum, massa nisl semper ipsum,\n"
"vestibulum sodales sem ante in massa.\n"
"Vestibulum in augue non felis convallis viverra.\n"
"Mauris ultricies dolor sed massa convallis sed aliquet augue fringilla.\n"
"Duis erat eros, porta in accumsan in, blandit quis sem.\n"
"In hac habitasse platea dictumst. Etiam fringilla est id odio dapibus sit amet semper dui laoreet.\n");
m_text.setCharacterSize(22);
m_text.setPosition({30.f, 20.f});
// Load the shader
return m_shader.loadFromFile("resources/wave.vert", "resources/blur.frag");
}
void onUpdate(float time, float x, float y) override
{
m_shader.setUniform("wave_phase", time);
m_shader.setUniform("wave_amplitude", sf::Vector2f(x * 40, y * 40));
m_shader.setUniform("blur_radius", (x + y) * 0.008f);
}
void onDraw(sf::RenderTarget& target, const sf::RenderStates& states) const override
{
sf::RenderStates statesCopy(states);
statesCopy.shader = &m_shader;
target.draw(m_text, statesCopy);
}
private:
sf::Text m_text;
sf::Shader m_shader;
};
////////////////////////////////////////////////////////////
// "Storm" vertex shader + "blink" fragment shader
////////////////////////////////////////////////////////////
class StormBlink : public Effect
{
public:
StormBlink() : Effect("Storm + Blink")
{
}
bool onLoad() override
{
std::uniform_real_distribution<float> xDistribution(0, 800);
std::uniform_real_distribution<float> yDistribution(0, 600);
std::uniform_int_distribution<std::uint16_t> colorDistribution(0, 255);
// Create the points
m_points.setPrimitiveType(sf::PrimitiveType::Points);
for (int i = 0; i < 40000; ++i)
{
const auto x = xDistribution(rng);
const auto y = yDistribution(rng);
const auto r = static_cast<std::uint8_t>(colorDistribution(rng));
const auto g = static_cast<std::uint8_t>(colorDistribution(rng));
const auto b = static_cast<std::uint8_t>(colorDistribution(rng));
m_points.append(sf::Vertex(sf::Vector2f(x, y), sf::Color(r, g, b)));
}
// Load the shader
return m_shader.loadFromFile("resources/storm.vert", "resources/blink.frag");
}
void onUpdate(float time, float x, float y) override
{
const float radius = 200 + std::cos(time) * 150;
m_shader.setUniform("storm_position", sf::Vector2f(x * 800, y * 600));
m_shader.setUniform("storm_inner_radius", radius / 3);
m_shader.setUniform("storm_total_radius", radius);
m_shader.setUniform("blink_alpha", 0.5f + std::cos(time * 3) * 0.25f);
}
void onDraw(sf::RenderTarget& target, const sf::RenderStates& states) const override
{
sf::RenderStates statesCopy(states);
statesCopy.shader = &m_shader;
target.draw(m_points, statesCopy);
}
private:
sf::VertexArray m_points;
sf::Shader m_shader;
};
////////////////////////////////////////////////////////////
// "Edge" post-effect fragment shader
////////////////////////////////////////////////////////////
class Edge : public Effect
{
public:
Edge() : Effect("Edge Post-effect")
{
}
bool onLoad() override
{
// Create the off-screen surface
if (!m_surface.create({800, 600}))
return false;
m_surface.setSmooth(true);
// Load the textures
if (!m_backgroundTexture.loadFromFile("resources/sfml.png"))
return false;
m_backgroundTexture.setSmooth(true);
if (!m_entityTexture.loadFromFile("resources/devices.png"))
return false;
m_entityTexture.setSmooth(true);
// Initialize the background sprite
m_backgroundSprite.emplace(m_backgroundTexture);
m_backgroundSprite->setPosition({135.f, 100.f});
// Load the moving entities
for (int i = 0; i < 6; ++i)
{
const sf::Sprite entity(m_entityTexture, sf::IntRect({96 * i, 0}, {96, 96}));
m_entities.push_back(entity);
}
// Load the shader
if (!m_shader.loadFromFile("resources/edge.frag", sf::Shader::Fragment))
return false;
m_shader.setUniform("texture", sf::Shader::CurrentTexture);
return true;
}
void onUpdate(float time, float x, float y) override
{
m_shader.setUniform("edge_threshold", 1 - (x + y) / 2);
// Update the position of the moving entities
for (std::size_t i = 0; i < m_entities.size(); ++i)
{
sf::Vector2f position;
position.x = std::cos(0.25f * (time * static_cast<float>(i) + static_cast<float>(m_entities.size() - i))) * 300 +
350;
position.y = std::sin(0.25f * (time * static_cast<float>(m_entities.size() - i) + static_cast<float>(i))) * 200 +
250;
m_entities[i].setPosition(position);
}
// Render the updated scene to the off-screen surface
m_surface.clear(sf::Color::White);
m_surface.draw(*m_backgroundSprite);
for (const sf::Sprite& entity : m_entities)
m_surface.draw(entity);
m_surface.display();
}
void onDraw(sf::RenderTarget& target, const sf::RenderStates& states) const override
{
sf::RenderStates statesCopy(states);
statesCopy.shader = &m_shader;
target.draw(sf::Sprite(m_surface.getTexture()), statesCopy);
}
private:
sf::RenderTexture m_surface;
sf::Texture m_backgroundTexture;
sf::Texture m_entityTexture;
std::optional<sf::Sprite> m_backgroundSprite;
std::vector<sf::Sprite> m_entities;
sf::Shader m_shader;
};
////////////////////////////////////////////////////////////
// "Geometry" geometry shader example
////////////////////////////////////////////////////////////
class Geometry : public Effect
{
public:
Geometry() : Effect("Geometry Shader Billboards"), m_pointCloud(sf::PrimitiveType::Points, 10000)
{
}
bool onLoad() override
{
// Check if geometry shaders are supported
if (!sf::Shader::isGeometryAvailable())
return false;
// Move the points in the point cloud to random positions
for (std::size_t i = 0; i < 10000; ++i)
{
// Spread the coordinates from -480 to +480
// So they'll always fill the viewport at 800x600
std::uniform_real_distribution<float> positionDistribution(-480, 480);
m_pointCloud[i].position = {positionDistribution(rng), positionDistribution(rng)};
}
// Load the texture
if (!m_logoTexture.loadFromFile("resources/logo.png"))
return false;
// Load the shader
if (!m_shader.loadFromFile("resources/billboard.vert", "resources/billboard.geom", "resources/billboard.frag"))
return false;
m_shader.setUniform("texture", sf::Shader::CurrentTexture);
// Set the render resolution (used for proper scaling)
m_shader.setUniform("resolution", sf::Vector2f(800, 600));
return true;
}
void onUpdate(float /*time*/, float x, float y) override
{
// Reset our transformation matrix
m_transform = sf::Transform::Identity;
// Move to the center of the window
m_transform.translate({400.f, 300.f});
// Rotate everything based on cursor position
m_transform.rotate(sf::degrees(x * 360.f));
// Adjust billboard size to scale between 25 and 75
const float size = 25 + std::abs(y) * 50;
// Update the shader parameter
m_shader.setUniform("size", sf::Vector2f(size, size));
}
void onDraw(sf::RenderTarget& target, const sf::RenderStates& states) const override
{
sf::RenderStates statesCopy(states);
// Prepare the render state
statesCopy.shader = &m_shader;
statesCopy.texture = &m_logoTexture;
statesCopy.transform = m_transform;
// Draw the point cloud
target.draw(m_pointCloud, statesCopy);
}
private:
sf::Texture m_logoTexture;
sf::Transform m_transform;
sf::Shader m_shader;
sf::VertexArray m_pointCloud;
};
////////////////////////////////////////////////////////////
/// Entry point of application
///
/// \return Application exit code
///
////////////////////////////////////////////////////////////
int main()
{
// Create the main window
sf::RenderWindow window(sf::VideoMode({800, 600}), "SFML Shader", sf::Style::Titlebar | sf::Style::Close);
window.setVerticalSyncEnabled(true);
// Load the application font and pass it to the Effect class
sf::Font font;
if (!font.loadFromFile("resources/tuffy.ttf"))
return EXIT_FAILURE;
Effect::setFont(font);
// Create the effects
Pixelate pixelateEffect;
WaveBlur waveBlurEffect;
StormBlink stormBlinkEffect;
Edge edgeEffect;
Geometry geometryEffect;
const std::array<Effect*, 5> effects{&pixelateEffect, &waveBlurEffect, &stormBlinkEffect, &edgeEffect, &geometryEffect};
std::size_t current = 0;
// Initialize them
for (Effect* effect : effects)
effect->load();
// Create the messages background
sf::Texture textBackgroundTexture;
if (!textBackgroundTexture.loadFromFile("resources/text-background.png"))
return EXIT_FAILURE;
sf::Sprite textBackground(textBackgroundTexture);
textBackground.setPosition({0.f, 520.f});
textBackground.setColor(sf::Color(255, 255, 255, 200));
// Create the description text
sf::Text description(font, "Current effect: " + effects[current]->getName(), 20);
description.setPosition({10.f, 530.f});
description.setFillColor(sf::Color(80, 80, 80));
// Create the instructions text
sf::Text instructions(font, "Press left and right arrows to change the current shader", 20);
instructions.setPosition({280.f, 555.f});
instructions.setFillColor(sf::Color(80, 80, 80));
// Start the game loop
const sf::Clock clock;
while (window.isOpen())
{
// Process events
for (sf::Event event; window.pollEvent(event);)
{
// Close window: exit
if (event.is<sf::Event::Closed>())
window.close();
if (const auto* keyPressed = event.getIf<sf::Event::KeyPressed>())
{
switch (keyPressed->code)
{
// Escape key: exit
case sf::Keyboard::Escape:
window.close();
break;
// Left arrow key: previous shader
case sf::Keyboard::Left:
if (current == 0)
current = effects.size() - 1;
else
--current;
description.setString("Current effect: " + effects[current]->getName());
break;
// Right arrow key: next shader
case sf::Keyboard::Right:
if (current == effects.size() - 1)
current = 0;
else
++current;
description.setString("Current effect: " + effects[current]->getName());
break;
default:
break;
}
}
}
// Update the current example
const auto [x, y] = sf::Vector2f(sf::Mouse::getPosition(window)).cwiseDiv(sf::Vector2f(window.getSize()));
effects[current]->update(clock.getElapsedTime().asSeconds(), x, y);
// Clear the window
if (effects[current]->getName() == "Edge Post-effect")
{
window.clear(sf::Color::White);
}
else
{
window.clear(sf::Color(50, 50, 50));
}
// Draw the current example
window.draw(*effects[current]);
// Draw the text
window.draw(textBackground);
window.draw(instructions);
window.draw(description);
// Finally, display the rendered frame on screen
window.display();
}
}