blah.cpp

#include <windows.h>
#include <GL/gl.h>

#define XRES    1366
#define YRES     768

//~ #define USEWIN

#define GLExt(a) a(wglGetProcAddress(#a))

extern "C" {
	typedef void(__stdcall*glUseProgram)(int);
	typedef int(__stdcall*glCreateProgram)(void);
	typedef int(__stdcall*glCreateShader)(int);
	typedef void(__stdcall*glLinkProgram)(int);
	typedef void(__stdcall*glCompileShader)(int);
	typedef void(__stdcall*glAttachShader)(int,int);
	typedef void(__stdcall*glShaderSource)(unsigned shader, int count, char** string, const int *length);
}

void entrypoint( void ) {
	const static PIXELFORMATDESCRIPTOR pfd = {0,0,PFD_SUPPORT_OPENGL|PFD_DOUBLEBUFFER};

#ifdef USEWIN
    const auto hDC = GetDC(CreateWindow("edit", 0, WS_POPUP|WS_VISIBLE|WS_MAXIMIZE, 0,0,0,0,0,0,0,0));
	ShowCursor( 0 );
#else
	const auto hDC = GetDC(nullptr);
	SetCursorPos(0,YRES);
#endif

    SetPixelFormat(hDC, ChoosePixelFormat(hDC, &pfd), &pfd);
    wglMakeCurrent(hDC, wglCreateContext(hDC));

    const auto p = GLExt(glCreateProgram)();
    const auto s = GLExt(glCreateShader)(0x8B30);
	const auto starttime = GetTickCount();

    do {
		char *pflog;

		wsprintf(pflog, "void main(void) {"
			"float time = %d. / 1000.;"
			"float t = time, p;"
			"vec2 g = gl_FragCoord.xy, s = vec2(1366.,768.), u = (g+g-s)/s.y, ar = vec2(atan(u.x, u.y) * 3.18 + t*2., length(u)*3. + fract(t*.5)*4.);"
			"p = floor(ar.y)/5.;"
			"ar = abs(fract(ar)-.5);"
			"gl_FragColor = mix(vec4(1,.3,0,1), vec4(.3,.2,.5,1), vec4(fract((p)))) * .1/dot(ar,ar);"
			"gl_FragColor.a = 1.;"
		"}", GetTickCount() - starttime);

		char *blorg = pflog;

		GLExt(glShaderSource)(s, 1, &blorg, 0);

		GLExt(glCompileShader)(s);
		GLExt(glAttachShader)(p,s);
		GLExt(glLinkProgram)(p);
		GLExt(glUseProgram)(p);

        glRects(-1,-1,1,1);
        SwapBuffers(hDC);
    }while ( !GetAsyncKeyState(VK_ESCAPE) );

    ExitProcess( 0 );
}