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////////////////////////////////////////////////////////////
// Headers
////////////////////////////////////////////////////////////
#include <SFML/Graphics.hpp>
#include <SFML/OpenGL.hpp>
#ifndef GL_SRGB8_ALPHA8
#define GL_SRGB8_ALPHA8 0x8C43
#endif
////////////////////////////////////////////////////////////
/// Entry point of application
///
/// \return Application exit code
///
////////////////////////////////////////////////////////////
int main()
{
bool exit = false;
bool sRgb = false;
while (!exit)
{
// Request a 24-bits depth buffer when creating the window
sf::ContextSettings contextSettings;
contextSettings.depthBits = 24;
contextSettings.sRgbCapable = sRgb;
// Create the main window
sf::RenderWindow window(sf::VideoMode(800, 600), "SFML graphics with OpenGL", sf::Style::Default, contextSettings);
window.setVerticalSyncEnabled(true);
// Create a sprite for the background
sf::Texture backgroundTexture;
backgroundTexture.setSrgb(sRgb);
if (!backgroundTexture.loadFromFile("resources/background.jpg"))
return EXIT_FAILURE;
sf::Sprite background(backgroundTexture);
// Create some text to draw on top of our OpenGL object
sf::Font font;
if (!font.loadFromFile("resources/sansation.ttf"))
return EXIT_FAILURE;
sf::Text text("SFML / OpenGL demo", font);
sf::Text sRgbInstructions("Press space to toggle sRGB conversion", font);
sf::Text mipmapInstructions("Press return to toggle mipmapping", font);
text.setFillColor(sf::Color(255, 255, 255, 170));
sRgbInstructions.setFillColor(sf::Color(255, 255, 255, 170));
mipmapInstructions.setFillColor(sf::Color(255, 255, 255, 170));
text.setPosition(250.f, 450.f);
sRgbInstructions.setPosition(150.f, 500.f);
mipmapInstructions.setPosition(180.f, 550.f);
// Load a texture to apply to our 3D cube
sf::Texture texture;
if (!texture.loadFromFile("resources/texture.jpg"))
return EXIT_FAILURE;
// Attempt to generate a mipmap for our cube texture
// We don't check the return value here since
// mipmapping is purely optional in this example
texture.generateMipmap();
// Make the window the active window for OpenGL calls
window.setActive(true);
// Enable Z-buffer read and write
glEnable(GL_DEPTH_TEST);
glDepthMask(GL_TRUE);
glClearDepth(1.f);
// Disable lighting
glDisable(GL_LIGHTING);
// Configure the viewport (the same size as the window)
glViewport(0, 0, window.getSize().x, window.getSize().y);
// Setup a perspective projection
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
GLfloat ratio = static_cast<float>(window.getSize().x) / window.getSize().y;
glFrustum(-ratio, ratio, -1.f, 1.f, 1.f, 500.f);
// Bind the texture
glEnable(GL_TEXTURE_2D);
sf::Texture::bind(&texture);
// Define a 3D cube (6 faces made of 2 triangles composed by 3 vertices)
static const GLfloat cube[] =
{
// positions // texture coordinates
-20, -20, -20, 0, 0,
-20, 20, -20, 1, 0,
-20, -20, 20, 0, 1,
-20, -20, 20, 0, 1,
-20, 20, -20, 1, 0,
-20, 20, 20, 1, 1,
20, -20, -20, 0, 0,
20, 20, -20, 1, 0,
20, -20, 20, 0, 1,
20, -20, 20, 0, 1,
20, 20, -20, 1, 0,
20, 20, 20, 1, 1,
-20, -20, -20, 0, 0,
20, -20, -20, 1, 0,
-20, -20, 20, 0, 1,
-20, -20, 20, 0, 1,
20, -20, -20, 1, 0,
20, -20, 20, 1, 1,
-20, 20, -20, 0, 0,
20, 20, -20, 1, 0,
-20, 20, 20, 0, 1,
-20, 20, 20, 0, 1,
20, 20, -20, 1, 0,
20, 20, 20, 1, 1,
-20, -20, -20, 0, 0,
20, -20, -20, 1, 0,
-20, 20, -20, 0, 1,
-20, 20, -20, 0, 1,
20, -20, -20, 1, 0,
20, 20, -20, 1, 1,
-20, -20, 20, 0, 0,
20, -20, 20, 1, 0,
-20, 20, 20, 0, 1,
-20, 20, 20, 0, 1,
20, -20, 20, 1, 0,
20, 20, 20, 1, 1
};
// Enable position and texture coordinates vertex components
glEnableClientState(GL_VERTEX_ARRAY);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);
glVertexPointer(3, GL_FLOAT, 5 * sizeof(GLfloat), cube);
glTexCoordPointer(2, GL_FLOAT, 5 * sizeof(GLfloat), cube + 3);
// Disable normal and color vertex components
glDisableClientState(GL_NORMAL_ARRAY);
glDisableClientState(GL_COLOR_ARRAY);
// Make the window no longer the active window for OpenGL calls
window.setActive(false);
// Create a clock for measuring the time elapsed
sf::Clock clock;
// Flag to track whether mipmapping is currently enabled
bool mipmapEnabled = true;
// Start game loop
while (window.isOpen())
{
// Process events
sf::Event event;
while (window.pollEvent(event))
{
// Close window: exit
if (event.type == sf::Event::Closed)
{
exit = true;
window.close();
}
// Escape key: exit
if ((event.type == sf::Event::KeyPressed) && (event.key.code == sf::Keyboard::Escape))
{
exit = true;
window.close();
}
// Return key: toggle mipmapping
if ((event.type == sf::Event::KeyPressed) && (event.key.code == sf::Keyboard::Enter))
{
if (mipmapEnabled)
{
// We simply reload the texture to disable mipmapping
if (!texture.loadFromFile("resources/texture.jpg"))
return EXIT_FAILURE;
mipmapEnabled = false;
}
else
{
texture.generateMipmap();
mipmapEnabled = true;
}
}
// Space key: toggle sRGB conversion
if ((event.type == sf::Event::KeyPressed) && (event.key.code == sf::Keyboard::Space))
{
sRgb = !sRgb;
window.close();
}
// Adjust the viewport when the window is resized
if (event.type == sf::Event::Resized)
{
// Make the window the active window for OpenGL calls
window.setActive(true);
glViewport(0, 0, event.size.width, event.size.height);
// Make the window no longer the active window for OpenGL calls
window.setActive(false);
}
}
// Draw the background
window.pushGLStates();
window.draw(background);
window.popGLStates();
// Make the window the active window for OpenGL calls
window.setActive(true);
// Clear the depth buffer
glClear(GL_DEPTH_BUFFER_BIT);
// We get the position of the mouse cursor, so that we can move the box accordingly
float x = sf::Mouse::getPosition(window).x * 200.f / window.getSize().x - 100.f;
float y = -sf::Mouse::getPosition(window).y * 200.f / window.getSize().y + 100.f;
// Apply some transformations
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glTranslatef(x, y, -100.f);
glRotatef(clock.getElapsedTime().asSeconds() * 50.f, 1.f, 0.f, 0.f);
glRotatef(clock.getElapsedTime().asSeconds() * 30.f, 0.f, 1.f, 0.f);
glRotatef(clock.getElapsedTime().asSeconds() * 90.f, 0.f, 0.f, 1.f);
// Draw the cube
glDrawArrays(GL_TRIANGLES, 0, 36);
// Make the window no longer the active window for OpenGL calls
window.setActive(false);
// Draw some text on top of our OpenGL object
window.pushGLStates();
window.draw(text);
window.draw(sRgbInstructions);
window.draw(mipmapInstructions);
window.popGLStates();
// Finally, display the rendered frame on screen
window.display();
}
}
return EXIT_SUCCESS;
}
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