func InitSimulation() bool {
// Load texture
texObjects = LoadTexture("objects.png")
if texObjects == nil {
return false
}
rand = New(0)
// Create sprites
sky = sprite.New(nil, 0, 0, SCREEN_WIDTH, SKY_HEIGHT)
sea = dist.New(SEA_SUBDIVISION, SEA_SUBDIVISION)
sea.SetTextureRect(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT-SKY_HEIGHT)
sun = sprite.New(texObjects, 81, 0, 114, 114)
sun.SetHotSpot(57, 57)
moon = sprite.New(texObjects, 0, 0, 81, 81)
moon.SetHotSpot(40, 40)
star = sprite.New(texObjects, 72, 81, 9, 9)
star.SetHotSpot(5, 5)
glow = sprite.New(texObjects, 128, 128, 128, 128)
glow.SetHotSpot(64, 64)
glow.SetBlendMode(BLEND_COLORADD | BLEND_ALPHABLEND | BLEND_NOZWRITE)
seaglow = sprite.New(texObjects, 128, 224, 128, 32)
seaglow.SetHotSpot(64, 0)
seaglow.SetBlendMode(BLEND_COLORADD | BLEND_ALPHAADD | BLEND_NOZWRITE)
// Initialize simulation state
colWhite.SetHWColor(0xFFFFFFFF)
timet = GetTime()
speed = 0.0
for i := 0; i < NUM_STARS; i++ { // star positions
starX[i] = rand.Float64(0, SCREEN_WIDTH)
starY[i] = rand.Float64(0, STARS_HEIGHT)
starS[i] = rand.Float64(0.1, 0.7)
}
for i := 0; i < SEA_SUBDIVISION; i++ { // sea waves phase shifts
seaP[i] = float64(i) + rand.Float64(-15.0, 15.0)
}
// Systems are ready now!
return true
}
func UpdateSimulation() {
cellw := SCREEN_WIDTH / (SEA_SUBDIVISION - 1)
var col1, col2 color.ColorRGB
// Update time of day
if speed == 0.0 {
timet = GetTime()
} else {
timet += Delta() * speed
if timet >= 24.0 {
timet -= 24.0
}
}
seq_id = int(timet / 3)
seq_residue = timet/3 - float64(seq_id)
zenith := -(timet/12.0*hge.Pi - hge.Pi_2)
// Interpolate sea and sky colors
col1.SetHWColor(skyTopColors[seq[seq_id]])
col2.SetHWColor(skyTopColors[seq[seq_id+1]])
colSkyTop = col2.MulScalar(seq_residue).Add(col1.MulScalar(1.0 - seq_residue))
col1.SetHWColor(skyBtmColors[seq[seq_id]])
col2.SetHWColor(skyBtmColors[seq[seq_id+1]])
colSkyBtm = col2.MulScalar(seq_residue).Add(col1.MulScalar(1.0 - seq_residue))
col1.SetHWColor(seaTopColors[seq[seq_id]])
col2.SetHWColor(seaTopColors[seq[seq_id+1]])
colSeaTop = col2.MulScalar(seq_residue).Add(col1.MulScalar(1.0 - seq_residue))
col1.SetHWColor(seaBtmColors[seq[seq_id]])
col2.SetHWColor(seaBtmColors[seq[seq_id+1]])
colSeaBtm = col2.MulScalar(seq_residue).Add(col1.MulScalar(1.0 - seq_residue))
var a float64
// Update stars
if seq_id >= 6 || seq_id < 2 {
for i := 0; i < NUM_STARS; i++ {
a = 1.0 - starY[i]/STARS_HEIGHT
a *= rand.Float64(0.6, 1.0)
if seq_id >= 6 {
a *= math.Sin((timet - 18.0) / 6.0 * hge.Pi_2)
} else {
a *= math.Sin((1.0 - timet/6.0) * hge.Pi_2)
}
starA[i] = a
}
}
// Calculate sun position, scale and colors
if seq_id == 2 {
a = math.Sin(seq_residue * hge.Pi_2)
} else if seq_id == 5 {
a = math.Cos(seq_residue * hge.Pi_2)
} else if seq_id > 2 && seq_id < 5 {
a = 1.0
} else {
a = 0.0
}
colSun.SetHWColor(0xFFEAE1BE)
colSun = colSun.MulScalar(1 - a).Add(colWhite.MulScalar(a))
a = (math.Cos(timet/6.0*hge.Pi) + 1.0) / 2.0
if seq_id >= 2 && seq_id <= 6 {
colSunGlow = colWhite.MulScalar(a)
colSunGlow.A = 1.0
} else {
colSunGlow.SetHWColor(0xFF000000)
}
sunX = SCREEN_WIDTH*0.5 + math.Cos(zenith)*ORBITS_RADIUS
sunY = SKY_HEIGHT*1.2 + math.Sin(zenith)*ORBITS_RADIUS
sunS = 1.0 - 0.3*math.Sin((timet-6.0)/12.0*hge.Pi)
sunGlowS = 3.0*(1.0-a) + 3.0
// Calculate moon position, scale and colors
if seq_id >= 6 {
a = math.Sin((timet - 18.0) / 6.0 * hge.Pi_2)
} else {
a = math.Sin((1.0 - timet/6.0) * hge.Pi_2)
}
colMoon.SetHWColor(0x20FFFFFF)
colMoon = colMoon.MulScalar(1 - a).Add(colWhite.MulScalar(a))
colMoonGlow = colWhite
colMoonGlow.A = 0.5 * a
moonX = SCREEN_WIDTH*0.5 + math.Cos(zenith-hge.Pi)*ORBITS_RADIUS
moonY = SKY_HEIGHT*1.2 + math.Sin(zenith-hge.Pi)*ORBITS_RADIUS
moonS = 1.0 - 0.3*math.Sin((timet+6.0)/12.0*hge.Pi)
moonGlowS = a*0.4 + 0.5
// Calculate sea glow
if timet > 19.0 || timet < 4.5 { // moon
a = 0.2 // intensity
if timet > 19.0 && timet < 20.0 {
a *= (timet - 19.0)
} else if timet > 3.5 && timet < 4.5 {
a *= 1.0 - (timet - 3.5)
}
colSeaGlow = colMoonGlow
colSeaGlow.A = a
seaGlowX = moonX
seaGlowSX = moonGlowS * 3.0
seaGlowSY = moonGlowS * 2.0
} else if timet > 6.5 && timet < 19.0 { // sun
a = 0.3 // intensity
if timet < 7.5 {
a *= (timet - 6.5)
} else if timet > 18.0 {
a *= 1.0 - (timet - 18.0)
}
colSeaGlow = colSunGlow
colSeaGlow.A = a
seaGlowX = sunX
seaGlowSX = sunGlowS
seaGlowSY = sunGlowS * 0.6
} else {
colSeaGlow.A = 0.0
}
var dwCol1 hge.Dword
// Move waves and update sea color
for i := 1; i < SEA_SUBDIVISION-1; i++ {
a = float64(i) / (SEA_SUBDIVISION - 1)
col1 = colSeaTop.MulScalar(1 - a).Add(colSeaBtm.MulScalar(a))
dwCol1 = col1.HWColor()
fTime := 2.0 * Time()
a *= 20
for j := 0; j < SEA_SUBDIVISION; j++ {
sea.SetColor(j, i, dwCol1)
dy := a * math.Sin(seaP[i]+(float64(j)/(SEA_SUBDIVISION-1)-0.5)*hge.Pi*16.0-fTime)
sea.SetDisplacement(j, i, 0.0, dy, dist.DISP_NODE)
}
}
dwCol1 = colSeaTop.HWColor()
dwCol2 := colSeaBtm.HWColor()
for j := 0; j < SEA_SUBDIVISION; j++ {
sea.SetColor(j, 0, dwCol1)
sea.SetColor(j, SEA_SUBDIVISION-1, dwCol2)
}
var posX float64
// Calculate light path
if timet > 19.0 || timet < 5.0 { // moon
a = 0.12 // intensity
if timet > 19.0 && timet < 20.0 {
a *= (timet - 19.0)
} else if timet > 4.0 && timet < 5.0 {
a *= 1.0 - (timet - 4.0)
}
posX = moonX
} else if timet > 7.0 && timet < 17.0 { // sun
a = 0.14 // intensity
if timet < 8.0 {
a *= (timet - 7.0)
} else if timet > 16.0 {
a *= 1.0 - (timet - 16.0)
}
posX = sunX
} else {
a = 0.0
}
if a != 0.0 {
k := int(math.Floor(posX / float64(cellw)))
s1 := (1.0 - (posX-float64(k*cellw))/float64(cellw))
s2 := (1.0 - (float64((k+1)*cellw)-posX)/float64(cellw))
if s1 > 0.7 {
s1 = 0.7
}
if s2 > 0.7 {
s2 = 0.7
}
s1 *= a
s2 *= a
for i := 0; i < SEA_SUBDIVISION; i += 2 {
a = math.Sin(float64(i) / (SEA_SUBDIVISION - 1) * hge.Pi_2)
col1.SetHWColor(sea.Color(k, i))
col1.AddEqual(colSun.MulScalar(s1 * (1 - a)))
col1.Clamp()
sea.SetColor(k, i, col1.HWColor())
col1.SetHWColor(sea.Color(k+1, i))
col1.AddEqual(colSun.MulScalar(s2 * (1 - a)))
col1.Clamp()
sea.SetColor(k+1, i, col1.HWColor())
}
}
}