func (p *Planetoid) Render(dp float64) {
glh.With(glh.Matrix{gl.MODELVIEW}, func() {
gl.Rotated(p.rising_node, 0, 1, 0)
gl.Rotated(p.inclination, 0, 0, 1)
gl.Rotated(p.phase0+p.phase, 0, 1, 0)
p.phase += dp*10 + (1 - p.apogee)
glh.With(glh.Matrix{gl.MODELVIEW}, func() {
// TODO: Compute position correctly
gl.Translated(p.apogee, 0, 0)
Sphere(p.radius, 3)
})
// TODO: Avoid depth thrashing when trails overlap
// Trail
glh.With(glh.Matrix{gl.MODELVIEW}, func() {
gl.Rotated(90, 1, 0, 0)
gl.Scaled(p.apogee, p.apogee, 1)
gl.LineWidth(2)
glh.With(glh.Disable(gl.LIGHTING), func() {
p.circle.Render(gl.LINE_STRIP)
})
})
})
}
func PlaceObject(compiledPrim gl.List, scale [3]double, translation [3]double, rotation [4]double) {
// objects are placed and transformed when necessary
gl.PushMatrix()
gl.Scaled(scale)
gl.Translated(translation)
gl.Rotated(rotation)
gl.CallList(compiledPrim)
gl.PopMatrix()
}
func DrawEntity(en Entity) {
x := en.Xpos
y := en.Ypos
r := en.Rot
s := en.Size
col := en.Colour
switch col {
case "grey":
gl.Color3d(0.5, 0.5, 0.5)
case "red":
gl.Color3d(1, 0, 0)
case "green":
gl.Color3d(0, 1, 0)
case "blue":
gl.Color3d(0, 0, 1)
case "lblue":
gl.Color3d(0.3, 0.3, 1)
case "orange":
gl.Color3d(1, 0.5, 0)
case "yellow":
gl.Color3d(1, 1, 0)
case "purple":
gl.Color3d(1, 0, 1)
case "white":
gl.Color3d(1, 1, 1)
default:
gl.Color3d(1, 1, 1)
}
gl.PushMatrix()
gl.Translated(x, y, 0)
gl.Scaled(s, s, s)
//gl.Rotated(r*180/math.Pi, 0, 0, 1)
gl.Rotated(r, 0, 0, 1)
enx := [3]float64{-0.7, 0.7, 0}
eny := [3]float64{1, 1, -1}
//in OpenGL 3.2, the vertices below would be stored on the GPU
//so all you would need to do is say DrawShape(A) or something
gl.Begin(gl.TRIANGLES)
gl.Vertex3d(enx[0], eny[0], 0)
gl.Vertex3d(enx[1], eny[1], 0)
gl.Vertex3d(enx[2], eny[2], 0)
gl.End()
gl.PopMatrix()
}
// OpenGL draw function & timing
func draw() {
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
gl.PushMatrix()
gl.Rotated(view_rotx, 1.0, 0.0, 0.0)
gl.Rotated(view_roty, 0.0, 1.0, 0.0)
gl.Rotated(view_rotz, 0.0, 0.0, 1.0)
gl.PushMatrix()
gl.Translated(-3.0, -2.0, 0.0)
gl.Rotated(angle, 0.0, 0.0, 1.0)
gl.CallList(gear1)
gl.PopMatrix()
gl.PushMatrix()
gl.Translated(3.1, -2.0, 0.0)
gl.Rotated(-2.0*angle-9.0, 0.0, 0.0, 1.0)
gl.CallList(gear2)
gl.PopMatrix()
gl.PushMatrix()
gl.Translated(-3.1, 4.2, 0.0)
gl.Rotated(-2.0*angle-25.0, 0.0, 0.0, 1.0)
gl.CallList(gear3)
gl.PopMatrix()
gl.PopMatrix()
}
func draw() {
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
gl.PushMatrix()
gl.Rotated(view_rotx, 1.0, 0.0, 0.0)
gl.Rotated(view_roty, 0.0, 1.0, 0.0)
gl.Rotated(view_rotz, 0.0, 0.0, 1.0)
gl.PushMatrix()
gl.Translated(-3.0, -2.0, 0.0)
gl.Rotated(angle, 0.0, 0.0, 1.0)
gl.CallList(gear1)
gl.PopMatrix()
gl.PushMatrix()
gl.Translated(3.1, -2.0, 0.0)
gl.Rotated(-2.0*angle-9.0, 0.0, 0.0, 1.0)
gl.CallList(gear2)
gl.PopMatrix()
gl.PushMatrix()
gl.Translated(-3.1, 4.2, 0.0)
gl.Rotated(-2.0*angle-25.0, 0.0, 0.0, 1.0)
gl.CallList(gear3)
gl.PopMatrix()
gl.PopMatrix()
sdl.GL_SwapBuffers()
Frames++
{
t := sdl.GetTicks()
if t-T0 >= 5000 {
seconds := (t - T0) / 1000.0
fps := Frames / seconds
print(Frames, " frames in ", seconds, " seconds = ", fps, " FPS\n")
T0 = t
Frames = 0
}
}
}
func (p *Planetoid) RenderShadowVolume() {
glh.With(glh.Matrix{gl.MODELVIEW}, func() {
// gl.Rotated(90, 0, 1, 0)
gl.Rotated(p.rising_node, 0, 1, 0)
gl.Rotated(p.inclination, 0, 0, 1)
gl.Rotated(p.phase0+p.phase, 0, 1, 0)
// TODO: Compute position correctly
gl.Translated(p.apogee, 0, 0)
gl.Rotated(p.phase0+p.phase, 0, -1, 0)
gl.Rotated(p.inclination, 0, 0, -1)
gl.Rotated(p.rising_node, 0, -1, 0)
// gl.Rotated(p.phase0+p.phase, 0, -1, 0)
gl.Rotated(90, 0, -1, 0)
glu.Cylinder(quadric, p.radius, p.radius, 2, 10, 1)
})
}
func main() {
err := initGL()
if err != nil {
log.Printf("InitGL: %v", err)
return
}
defer glfw.Terminate()
mb := createBuffer()
defer mb.Release()
gl.Enable(gl.BLEND)
//gl.BlendFunc(gl.SRC_ALPHA, gl.ONE)
gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
f, err := os.Create("test.mpeg")
if err != nil {
log.Panicf("Unable to open output file: %q", err)
}
im := image.NewRGBA(image.Rect(0, 0, 512, 512))
e, err := ffmpeg.NewEncoder(ffmpeg.CODEC_ID_H264, im, f)
if err != nil {
log.Panicf("Unable to start encoder: %q", err)
}
// Perform the rendering.
var angle float64
for glfw.WindowParam(glfw.Opened) > 0 {
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
gl.LoadIdentity()
gl.Translatef(0, 0, -6)
gl.Rotated(angle/10, 0, 1, 0)
gl.Rotated(angle, 1, 1, 1)
// Render a solid cube at half the scale.
gl.Scalef(0.1, 0.1, 0.1)
gl.Enable(gl.COLOR_MATERIAL)
gl.Enable(gl.POLYGON_OFFSET_FILL)
gl.PolygonMode(gl.FRONT_AND_BACK, gl.FILL)
mb.Render(gl.QUADS)
// Render wireframe cubes, with incremental size.
gl.Disable(gl.COLOR_MATERIAL)
gl.Disable(gl.POLYGON_OFFSET_FILL)
gl.PolygonMode(gl.FRONT_AND_BACK, gl.FILL)
for i := 0; i < 1000; i++ {
ifl := float64(i)
scale := 0.000005*ifl + 1.0 + 0.01*math.Sin(angle/10+ifl/10)
gl.Scaled(scale, scale, scale)
gl.Rotated((ifl+angle)/1000, 1, 1, 1)
gl.Rotated((ifl+angle)/1100, -1, 1, 1)
mb.Render(gl.QUADS)
}
glh.ClearAlpha(1)
glh.CaptureRGBA(im)
err := e.WriteFrame()
if err != nil {
panic(err)
}
angle += 0.5
//glh.CaptureToPng("test.png")
glfw.SwapBuffers()
}
e.Close()
}
func main() {
var err error
if err = glfw.Init(); err != nil {
fmt.Fprintf(os.Stderr, "[e] %v\n", err)
return
}
defer glfw.Terminate()
w, h := 1980, 1080
// w, h := 1280, 768
if err = glfw.OpenWindow(w, h, 8, 8, 8, 16, 0, 32, glfw.Fullscreen); err != nil {
fmt.Fprintf(os.Stderr, "[e] %v\n", err)
return
}
defer glfw.CloseWindow()
glfw.SetSwapInterval(1)
glfw.SetWindowTitle("Debris")
quadric = glu.NewQuadric()
gl.Enable(gl.CULL_FACE)
gl.Enable(gl.DEPTH_TEST)
gl.DepthFunc(gl.LEQUAL)
gl.Enable(gl.NORMALIZE)
gl.Enable(gl.BLEND)
gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
gl.ShadeModel(gl.SMOOTH)
gl.Enable(gl.LIGHTING)
var (
ambient = []float32{0.1, 0.3, 0.6, 1}
diffuse = []float32{1, 1, 0.5, 1}
specular = []float32{0.4, 0.4, 0.4, 1}
light_position = []float32{1, 0, 0, 0}
// mat_specular []float32 = []float32{1, 1, 0.5, 1}
mat_specular = []float32{1, 1, 0.75, 1}
mat_shininess = float32(120)
// light_position []float32 = []float32{0.0, 0.0, 1.0, 0.0}
)
const (
fov = 1.1 // degrees
znear = 145
zfar = 155
camera_z_offset = -150
camera_x_rotation = 0 // degrees
// camera_x_rotation = 20 // degrees
starfield_fov = 45
faces = 1000
earth_radius = 1
)
gl.Lightfv(gl.LIGHT1, gl.AMBIENT, ambient)
gl.Lightfv(gl.LIGHT1, gl.DIFFUSE, diffuse)
gl.Lightfv(gl.LIGHT1, gl.SPECULAR, specular)
gl.Lightfv(gl.LIGHT1, gl.POSITION, light_position)
gl.Enable(gl.LIGHT1)
mat_emission := []float32{0, 0, 0.1, 1}
gl.Materialfv(gl.FRONT_AND_BACK, gl.EMISSION, mat_emission)
gl.Materialfv(gl.FRONT_AND_BACK, gl.SPECULAR, mat_specular)
gl.Materialf(gl.FRONT_AND_BACK, gl.SHININESS, mat_shininess)
gl.ClearColor(0.02, 0.02, 0.02, 1)
gl.ClearDepth(1)
gl.ClearStencil(0)
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
b := createBuffer()
planetoids := []*Planetoid{}
for i := 0; i < 1000; i++ {
p := &Planetoid{
apogee: 1.2 + rand.Float64()*0.7,
perigee: 1.5,
// inclination: 45,
inclination: rand.Float64()*20 - 10,
// inclination: 0,
phase0: rand.Float64() * 360,
rising_node: rand.Float64() * 10,
phase: 0,
// radius: rand.Float32()*0.05 + 0.01, //float32(r),
radius: rand.Float32()*0.0125 + 0.005, //float32(r),
// quadric: glu.NewQuadric(),
circle: b,
}
planetoids = append(planetoids, p)
}
// Initial projection matrix:
var aspect float64
glfw.SetWindowSizeCallback(func(w, h int) {
gl.Viewport(0, 0, w, h)
gl.MatrixMode(gl.PROJECTION)
gl.LoadIdentity()
aspect = float64(w) / float64(h)
glu.Perspective(fov, aspect, znear, zfar)
})
d := float64(0)
wireframe := false
atmosphere := false
polar := false
rotating := false
front := false
earth := true
cone := true
shadowing := true
tilt := false
running := true
glfw.SetKeyCallback(func(key, state int) {
if state != glfw.KeyPress {
// Don't act on key coming up
return
}
switch key {
case 'A':
atmosphere = !atmosphere
case 'C':
cone = !cone
case 'E':
earth = !earth
case 'R':
rotating = !rotating
case 'F':
front = !front
if front {
gl.FrontFace(gl.CW)
} else {
gl.FrontFace(gl.CCW)
}
case 'S':
shadowing = !shadowing
case 'T':
tilt = !tilt
case 'W':
wireframe = !wireframe
method := gl.GLenum(gl.FILL)
if wireframe {
method = gl.LINE
}
gl.PolygonMode(gl.FRONT_AND_BACK, method)
case glfw.KeyF2:
println("Screenshot captured")
// glh.CaptureToPng("screenshot.png")
w, h := glh.GetViewportWH()
im := image.NewRGBA(image.Rect(0, 0, w, h))
glh.ClearAlpha(1)
gl.Flush()
glh.CaptureRGBA(im)
go func() {
fd, err := os.Create("screenshot.png")
if err != nil {
panic("Unable to open file")
}
defer fd.Close()
png.Encode(fd, im)
}()
case 'Q', glfw.KeyEsc:
running = !running
case glfw.KeySpace:
polar = !polar
}
})
_ = rand.Float64
stars := glh.NewMeshBuffer(
glh.RenderArrays,
glh.NewPositionAttr(3, gl.DOUBLE, gl.STATIC_DRAW),
glh.NewColorAttr(3, gl.DOUBLE, gl.STATIC_DRAW))
const Nstars = 50000
points := make([]float64, 3*Nstars)
colors := make([]float64, 3*Nstars)
for i := 0; i < Nstars; i++ {
const R = 1
phi := rand.Float64() * 2 * math.Pi
z := R * (2*rand.Float64() - 1)
theta := math.Asin(z / R)
points[i*3+0] = R * math.Cos(theta) * math.Cos(phi)
points[i*3+1] = R * math.Cos(theta) * math.Sin(phi)
points[i*3+2] = z
const r = 0.8
v := rand.Float64()*r + (1 - r)
colors[i*3+0] = v
colors[i*3+1] = v
colors[i*3+2] = v
}
stars.Add(points, colors)
render_stars := func() {
glh.With(glh.Attrib{gl.DEPTH_BUFFER_BIT | gl.ENABLE_BIT}, func() {
gl.Disable(gl.LIGHTING)
gl.PointSize(1)
gl.Color4f(1, 1, 1, 1)
gl.Disable(gl.DEPTH_TEST)
gl.DepthMask(false)
stars.Render(gl.POINTS)
})
}
render_scene := func() {
// Update light position (sensitive to current modelview matrix)
gl.Lightfv(gl.LIGHT1, gl.POSITION, light_position)
gl.Lightfv(gl.LIGHT2, gl.POSITION, light_position)
if earth {
Sphere(earth_radius, faces)
}
unlit_points := glh.Compound(glh.Disable(gl.LIGHTING), glh.Primitive{gl.POINTS})
glh.With(unlit_points, func() {
gl.Vertex3d(1, 0, 0)
})
for _, p := range planetoids {
const dt = 0.1 // TODO: Frame update
p.Render(dt)
}
glh.With(glh.Disable(gl.LIGHTING), func() {
// Atmosphere
gl.Color4f(0.25, 0.25, 1, 0.1)
if atmosphere && earth {
Sphere(earth_radius*1.025, 100)
}
gl.PointSize(10)
glh.With(glh.Primitive{gl.POINTS}, func() {
gl.Color4f(1.75, 0.75, 0.75, 1)
gl.Vertex3d(-1.04, 0, 0)
})
})
}
render_shadow_volume := func() {
glh.With(glh.Attrib{
gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT | gl.ENABLE_BIT |
gl.POLYGON_BIT | gl.STENCIL_BUFFER_BIT,
}, func() {
gl.Disable(gl.LIGHTING)
if shadowing {
// gl.Disable(gl.DEPTH_TEST)
gl.DepthMask(false)
gl.DepthFunc(gl.LEQUAL)
gl.Enable(gl.STENCIL_TEST)
gl.ColorMask(false, false, false, false)
gl.StencilFunc(gl.ALWAYS, 1, 0xffffffff)
}
shadow_volume := func() {
const sv_length = 2
const sv_granularity = 100
const sv_radius = earth_radius * 1.001
// Shadow cone
glh.With(glh.Matrix{gl.MODELVIEW}, func() {
gl.Rotatef(90, 1, 0, 0)
gl.Rotatef(90, 0, -1, 0)
gl.Color4f(0.5, 0.5, 0.5, 1)
glu.Cylinder(quadric, sv_radius, sv_radius*1.05,
sv_length, sv_granularity, 1)
glu.Disk(quadric, 0, sv_radius, sv_granularity, 1)
glh.With(glh.Matrix{gl.MODELVIEW}, func() {
gl.Translated(0, 0, sv_length)
glu.Disk(quadric, 0, sv_radius*1.05, sv_granularity, 1)
})
})
for _, p := range planetoids {
p.RenderShadowVolume()
}
}
if cone {
gl.FrontFace(gl.CCW)
gl.StencilOp(gl.KEEP, gl.KEEP, gl.INCR)
shadow_volume()
gl.FrontFace(gl.CW)
gl.StencilOp(gl.KEEP, gl.KEEP, gl.DECR)
shadow_volume()
}
if shadowing {
gl.StencilFunc(gl.NOTEQUAL, 0, 0xffffffff)
gl.StencilOp(gl.KEEP, gl.KEEP, gl.KEEP)
gl.ColorMask(true, true, true, true)
// gl.Disable(gl.STENCIL_TEST)
gl.Disable(gl.DEPTH_TEST)
gl.FrontFace(gl.CCW)
// gl.Color4f(1, 0, 0, 0.75)
gl.Color4f(0, 0, 0, 0.75)
// gl.Color4f(1, 1, 1, 0.75)
gl.LoadIdentity()
gl.Translated(0, 0, camera_z_offset)
// TODO: Figure out why this doesn't draw over the whole screen
glh.With(glh.Disable(gl.LIGHTING), func() {
glh.DrawQuadd(-10, -10, 20, 20)
})
// gl.FrontFace(gl.CW)
// gl.Enable(gl.LIGHTING)
// gl.Disable(gl.LIGHT1)
// render_scene()
// gl.Enable(gl.LIGHT1)
}
})
}
_ = render_stars
for running {
running = glfw.WindowParam(glfw.Opened) == 1
glfw.SwapBuffers()
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT | gl.STENCIL_BUFFER_BIT)
rotation := func() {
if tilt {
gl.Rotated(20, 1, 0, 0)
}
if polar {
gl.Rotated(90, 1, 0, 0)
}
gl.Rotated(d, 0, -1, 0)
}
// Star field
glh.With(glh.Matrix{gl.PROJECTION}, func() {
gl.LoadIdentity()
glu.Perspective(starfield_fov, aspect, 0, 1)
glh.With(glh.Matrix{gl.MODELVIEW}, func() {
gl.LoadIdentity()
rotation()
render_stars()
})
})
gl.MatrixMode(gl.MODELVIEW)
gl.LoadIdentity()
gl.Translated(0, 0, camera_z_offset)
rotation()
if rotating {
d += 0.2
}
_ = render_scene
render_scene()
_ = render_shadow_volume
render_shadow_volume()
}
}