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/*
alpha test example
*/
#include <ClanLib/core.h>
#include <ClanLib/jpeg.h>
#include <ClanLib/application.h>
#include <ClanLib/display.h>
class SurfaceApp : public CL_ClanApplication
{
public:
virtual char *get_title() { return "Alpha test application"; }
virtual int main(int, char **)
{
// Create a console window for text-output if not available
CL_ConsoleWindow console("Console");
console.redirect_stdio();
try
{
CL_SetupCore::init();
CL_SetupJPEG::init();
CL_SetupDisplay::init();
// Set mode: 640x480 16 bpp
CL_Display::set_videomode(640, 480, 16, false);
// Create a gradient surface
CL_Canvas *canvas = new CL_Canvas(100, 640);
canvas->lock();
unsigned int* data = (unsigned int*) canvas->get_data();
for (int y=0; y<480; y++)
{
for (int x=0; x<100; x++)
{
data[x + 100 * y] = CL_Color::get_color(RGBA8888,
1.0f,
0.0f,
0.0f,
float (y)/ 480.0f);
}
}
canvas->unlock();
CL_Surface *gradient = CL_Surface::create(canvas, true);
// Load surface from jpg file:
CL_Surface *surface = CL_JPEGProvider::create("back.jpg", NULL, RGB565);
float alpha = 0.0f;
// Loop until the user hits escape:
while (CL_Keyboard::get_keycode(CL_KEY_ESCAPE) == false)
{
// Draw surface
surface->put_screen(0, 0);
// Change the alpha
alpha += 0.01f;
if (alpha > 1.0)
alpha -= 1.0f;
// Draw some green alpha lines
for (int y = 10; y < 80; y += 10)
CL_Display::draw_line(0, y, 640, y, 0.0, 1.0, 0.0, 1.0f - alpha);
// Draw a blue alpha box
CL_Display::fill_rect(30, 30, 290, 170, 0.0, 0.0, 1.0, alpha);
// Draw the red gradient
gradient->put_screen(0,0);
// Flip front and backbuffer. This makes the changes visible:
CL_Display::flip_display();
// Update keyboard input and handle system events:
// Exits the loop if ClanLib requests shutdown - for instance if
// someone closes the window.
CL_System::keep_alive();
}
delete surface;
delete gradient;
// De-Initialize the ClanLib components
CL_SetupDisplay::deinit();
CL_SetupJPEG::deinit();
CL_SetupCore::deinit();
}
catch(CL_Error error)
{
std::cout << "Exception caught : " << error.message.c_str() << std::endl;
// Display console close message and wait for a key
console.display_close_message();
}
return 0;
}
} app;
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