func drawGrid(life *Life, nvg *nanovg.Context, refgrid [][]bool) {
w, h := float32(life.w), float32(life.h)
for y := float32(0); y < h; y++ {
for x := float32(0); x < w; x++ {
a, b := int(x), int(y)
c := life.a.s[b][a]
if refgrid[b][a] != c {
nvg.BeginPath()
nvg.Rect(x*5+1, y*5+1, 3, 3)
if c {
nvg.FillColor(nanovg.RGBA(255, 255, 255, 255))
} else {
nvg.FillColor(nanovg.RGBA(100, 100, 100, 255))
}
nvg.Fill()
nvg.ClosePath()
}
refgrid[b][a] = c
}
}
}
func StartGame() {
window := initSDL()
context := initGL(window)
nvg := initNanovg()
ww, wh := window.GetSize()
gw := ww / 5
gh := wh / 5
life := NewLife(gw, gh)
refgrid := make([][]bool, gh)
for i := range refgrid {
refgrid[i] = make([]bool, gw)
}
// Run the game at 15fps. This gives us about 66ms to calculate
// and render everything. 30ms is not possible yet.
minms := uint32(1000 / 15)
running := true
gl.ClearColor(0.3, 0.3, 0.32, 1.0)
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT | gl.STENCIL_BUFFER_BIT)
// Draw all squares first.
tw, th := float32(life.w), float32(life.h)
for y := float32(0); y < th; y++ {
for x := float32(0); x < tw; x++ {
nvg.BeginPath()
nvg.Rect(x*5+1, y*5+1, 3, 3)
nvg.FillColor(nanovg.RGBA(100, 100, 100, 255))
nvg.Fill()
nvg.ClosePath()
}
}
// Loop!
for running {
lt := sdl.GetTicks()
for event := sdl.PollEvent(); event != nil; event = sdl.PollEvent() {
switch t := event.(type) {
case *sdl.QuitEvent:
running = false
case *sdl.KeyUpEvent:
if t.Keysym.Sym == sdl.K_ESCAPE {
running = false
}
}
}
life.Step()
ww, wh := window.GetSize()
gl.Viewport(0, 0, ww, wh)
nvg.BeginFrame(ww, wh, 1.0)
drawGrid(life, nvg, refgrid)
nvg.EndFrame()
if d := sdl.GetTicks() - lt; d < minms {
sdl.Delay(minms - d)
}
sdl.GL_SwapWindow(window)
}
// Cleanup.
window.Destroy()
sdl.GL_DeleteContext(context)
nvg.Close()
sdl.Quit()
}