a594446ef0
Press key `I` (shift+`i`) to start a screen capture creating a gif with
the captured screen. Hit `I` again to stop the screen recording.
---
Add gif-h helper header only library
Copied from https://github.com/charlietangora/gif-h
3d2657b9ad
80 lines
2 KiB
C++
80 lines
2 KiB
C++
//
|
|
// gif-h-demo.cpp
|
|
// by Charlie Tangora
|
|
// Public domain.
|
|
// Email me : ctangora -at- gmail -dot- com
|
|
//
|
|
// Shows an example usage of gif.h
|
|
//
|
|
|
|
#include "gif.h"
|
|
|
|
#include <math.h>
|
|
|
|
const int width = 256;
|
|
const int height = 256;
|
|
uint8_t image[ width * height * 4 ];
|
|
|
|
void SetPixel( int xx, int yy, uint8_t red, uint8_t grn, uint8_t blu )
|
|
{
|
|
uint8_t* pixel = &image[(yy*width+xx)*4];
|
|
pixel[0] = red;
|
|
pixel[1] = blu;
|
|
pixel[2] = grn;
|
|
pixel[3] = 255; // no alpha for this demo
|
|
}
|
|
|
|
void SetPixelFloat( int xx, int yy, float fred, float fgrn, float fblu )
|
|
{
|
|
// convert float to unorm
|
|
uint8_t red = (uint8_t)roundf( 255.0f * fred );
|
|
uint8_t grn = (uint8_t)roundf( 255.0f * fgrn );
|
|
uint8_t blu = (uint8_t)roundf( 255.0f * fblu );
|
|
|
|
SetPixel( xx, yy, red, grn, blu );
|
|
}
|
|
|
|
int main(int argc, const char * argv[])
|
|
{
|
|
const char* filename = "./MyGif.gif";
|
|
if( argc > 1 )
|
|
{
|
|
filename = argv[1];
|
|
}
|
|
|
|
// Create a gif
|
|
GifWriter writer = {};
|
|
GifBegin( &writer, filename, width, height, 2, 8, true );
|
|
|
|
for( int frame=0; frame<256; ++frame )
|
|
{
|
|
|
|
// Make an image, somehow
|
|
// this is the default shadertoy - credit to shadertoy.com
|
|
float tt = frame * 3.14159f * 2 / 255.0f;
|
|
for( int yy=0; yy<height; ++yy )
|
|
{
|
|
for( int xx=0; xx<width; ++xx )
|
|
{
|
|
float fx = xx / (float)width;
|
|
float fy = yy / (float)height;
|
|
|
|
float red = 0.5f + 0.5f * cosf(tt+fx);
|
|
float grn = 0.5f + 0.5f * cosf(tt+fy+2.f);
|
|
float blu = 0.5f + 0.5f * cosf(tt+fx+4.f);
|
|
|
|
SetPixelFloat( xx, yy, red, grn, blu );
|
|
}
|
|
}
|
|
|
|
|
|
// Write the frame to the gif
|
|
printf( "Writing frame %d...\n", frame );
|
|
GifWriteFrame( &writer, image, width, height, 2, 8, true );
|
|
}
|
|
|
|
// Write EOF
|
|
GifEnd( &writer );
|
|
|
|
return 0;
|
|
}
|