Golang gl21.Float函数代码示例

// Creates a new system using (temorarily) hard-coded constants
func NewSystem(X, Y int) System {
	numStars := 1
	numPlanets := rand.Int() % 12

	// Make the slice of Planet

	planets := make([]*data.Planet, numPlanets+1)

	// TODO get rid of hard coded constants
	for i := 0; i <= numPlanets; i++ {
		orbitSizeX := rand.Float64()*4000 + 2000
		orbitSizeY := rand.Float64()*4000 + 2000
		orbitSpeed := rand.Float64() / ((orbitSizeX + orbitSizeY) / 10)

		size := gl.Float(rand.Float64() * 100)

		planets[i] = &data.Planet{data.GameObject{PlanetTextures[0], 0, 0, size, size, 0},
			orbitSizeX, orbitSizeY, orbitSpeed, float64(X), float64(Y)}
	}

	// Make the slice of Stars for each system
	stars := make([]*data.Star, numStars+1)

	for i := 0; i <= numStars; i++ {
		stars[i] = &data.Star{data.GameObject{PlanetTextures[0], gl.Float(X), gl.Float(Y), gl.Float(X + 300), gl.Float(Y + 300), 0}}
	}

	return System{X, Y, numStars, numPlanets, planets, stars}
}

func Cylinder(r, h gl.Float, slices int, hollow, solid bool) {
	res := 2 * math.Pi / float64(slices)
	mode := gl.LINE_LOOP
	if solid {
		mode = gl.QUADS
	}
	gl.Begin(gl.Enum(mode))
	for a := 0.0; a < 2*math.Pi; a += res {
		gl.Normal3f(gl.Float(math.Cos(a)), gl.Float(math.Sin(a)), 0)
		gl.Vertex3f(r*gl.Float(math.Cos(a)), r*gl.Float(math.Sin(a)), 0)
		gl.Vertex3f(r*gl.Float(math.Cos(a)), r*gl.Float(math.Sin(a)), h)
		a += res
		gl.Vertex3f(r*gl.Float(math.Cos(a)), r*gl.Float(math.Sin(a)), h)
		gl.Vertex3f(r*gl.Float(math.Cos(a)), r*gl.Float(math.Sin(a)), 0)
	}
	gl.End()
	if !hollow {
		// X Y plane
		if h < 0 {
			gl.Normal3f(0, 0, 1)
		} else {
			gl.Normal3f(0, 0, -1)
		}
		Circle(r, slices, solid)
		// Top (or bottom)
		if h < 0 {
			gl.Normal3f(0, 0, -1)
		} else {
			gl.Normal3f(0, 0, 1)
		}
		gl.Translatef(0, 0, h)
		Circle(r, slices, solid)
	}
}

func drawMatrix(m *[][]Point, xby, yby gl.Float) {
	for x, row := range *m {
		for y, p := range row {
			UseColor(PointColor(p))
			// fmt.Println(p, PointColor(p))
			// gl.Color4f(1, 0, 0, 1)
			gl.Vertex2f(gl.Float(x)*xby, gl.Float(y)*yby)
		}
	}
}

/* Updates o's position using its movement function.

The movemet function looks something like
	(x,y) = (f(t),g(t)) where for elliptic orbits

	f = Acos(t)
	g = Bsin(t)
*/
func PlanetOrbit(o *data.Planet, t float64) {
	A := o.OrbitParam1
	B := o.OrbitParam2
	C := o.OrbitParam3

	x0 := o.OrbitParam4
	y0 := o.OrbitParam5

	o.AbsMove(gl.Float(A*math.Sin(t*C)+x0), gl.Float(B*math.Cos(t*C)+y0))
}

func SetUniform4F(shader, variable string, vs []float32) error {
	prog, ok := shader_progs[shader]
	if !ok {
		return shaderError(fmt.Sprintf("Tried to set a uniform in an unknown shader '%s'", shader))
	}
	bvariable := []byte(fmt.Sprintf("%s\x00", variable))
	loc := gl.GetUniformLocation(prog, (*gl.Char)(unsafe.Pointer(&bvariable[0])))
	gl.Uniform4f(loc, gl.Float(vs[0]), gl.Float(vs[1]), gl.Float(vs[2]), gl.Float(vs[3]))
	return nil
}

func SetUniformV2(shader, variable string, v linear.Vec2) {
	prog, ok := shader_progs[shader]
	if !ok {
		if !warned_names[shader] {
			Warn().Printf("Tried to set a uniform in an unknown shader '%s'", shader)
			warned_names[shader] = true
		}
		return
	}
	bvariable := []byte(fmt.Sprintf("%s\x00", variable))
	loc := gl.GetUniformLocation(prog, (*gl.Char)(unsafe.Pointer(&bvariable[0])))
	gl.Uniform2f(loc, gl.Float(v.X), gl.Float(v.Y))
}

// SetVariable4f sets a specified variable to the four supplied integers to
// be passed into an effect.
func (effect *Effect) SetVariable4f(variable string, val1 float32, val2 float32, val3 float32, val4 float32) error {

	var currEffect gl.Int
	gl.GetIntegerv(gl.CURRENT_PROGRAM, &currEffect)
	if gl.Uint(currEffect) != effect.program {
		return errors.New("effect is not currently in use")
	}

	effect.checkUniformVariable(variable)

	gl.Uniform4f(effect.uniforms[variable], gl.Float(val1), gl.Float(val2), gl.Float(val3), gl.Float(val4))
	return nil
}

func Ellipse(rX, rY gl.Float, slices int, solid bool) {
	mode := gl.LINE_LOOP
	if solid {
		mode = gl.POLYGON
	}
	res := 2 * math.Pi / float64(slices)
	gl.Begin(gl.Enum(mode))
	gl.Vertex2f(0, 0)
	for a := 0.0; a < 2*math.Pi; a += res {
		gl.Vertex2f(rX*gl.Float(math.Cos(a)), rY*gl.Float(math.Sin(a)))
	}
	gl.End()
}

func Box(x, y, z float32, solid bool) {
	mode := gl.LINE_LOOP
	if solid {
		mode = gl.QUADS
	}
	X := gl.Float(x) / 2
	Y := gl.Float(y) / 2
	Z := gl.Float(z) / 2
	gl.Begin(gl.Enum(mode))

	gl.Normal3f(0, 0, 1) // Positive Z Face
	gl.Vertex3f(-X, -Y, Z)
	gl.Vertex3f(X, -Y, Z)
	gl.Vertex3f(X, Y, Z)
	gl.Vertex3f(-X, Y, Z)

	gl.Normal3f(0, 0, -1) // Negative Z Face
	gl.Vertex3f(-X, -Y, -Z)
	gl.Vertex3f(-X, Y, -Z)
	gl.Vertex3f(X, Y, -Z)
	gl.Vertex3f(X, -Y, -Z)

	gl.Normal3f(0, 1, 0) // Positive Y Face
	gl.Vertex3f(-X, Y, -Z)
	gl.Vertex3f(-X, Y, Z)
	gl.Vertex3f(X, Y, Z)
	gl.Vertex3f(X, Y, -Z)

	gl.Normal3f(0, -1, 0) // Negative Y Face
	gl.Vertex3f(-X, -Y, -Z)
	gl.Vertex3f(X, -Y, -Z)
	gl.Vertex3f(X, -Y, Z)
	gl.Vertex3f(-X, -Y, Z)

	gl.Normal3f(1, 0, 0) // Positive X Face
	gl.Vertex3f(X, -Y, -Z)
	gl.Vertex3f(X, Y, -Z)
	gl.Vertex3f(X, Y, Z)
	gl.Vertex3f(X, -Y, Z)

	gl.Normal3f(-1, 0, 0) // Negative X Face
	gl.Vertex3f(-X, -Y, -Z)
	gl.Vertex3f(-X, -Y, Z)
	gl.Vertex3f(-X, Y, Z)
	gl.Vertex3f(-X, Y, -Z)

	gl.End()
}

func drawScene() {
	fps()
	gl.Clear(gl.COLOR_BUFFER_BIT)

	gl.MatrixMode(gl.PROJECTION)
	gl.LoadIdentity()
	if input.Zoom > 0 {
		gl.Ortho(0, gl.Double(float64(*flagSize)/input.Zoom), gl.Double(float64(*flagSize)/input.Zoom), 0, -1, 1.0)
	}

	gl.MatrixMode(gl.MODELVIEW)
	gl.LoadIdentity()
	gl.Translatef(gl.Float(input.TransX*1), gl.Float(input.TransY*1), 0)
	drawGrid()
	drawCells()
}

func PointColor(p Point) Color {
	n := gl.Float(float64(p.Intensity) / 10.0)
	/*
	  if p.Color == WHITE {
	    return Color{1.0, 1.0, 1.0, 1}
	  }
	  if p.Color == RED {
	    return Color{1, 1-n, 1-n, 1}
	  }
	  if p.Color == GREEN {
	    return Color{1-n, 1, 1-n, 1}
	  }
	  return Color{1-n, 1-n, 1, 1}
	*/
	if p.Color == WHITE {
		return Color{0, 0, 0, 1}
	}
	if p.Color == RED {
		return Color{n, 0, 0, 1}
	}
	if p.Color == GREEN {
		return Color{0, n, 0, 1}
	}
	return Color{0, 0, n, 1}
}

func factor(t time.Time, tc0 time.Time, tc1 time.Time) gl.Float {
	num := t.Sub(tc0)
	den := tc1.Sub(tc0)
	res := num.Seconds() / den.Seconds()
	res = math.Max(res, 0)
	res = math.Min(res, 1)
	return gl.Float(res)
}

func SetUniformV2Array(shader, variable string, vs []linear.Vec2) {
	prog, ok := shader_progs[shader]
	if !ok {
		if !warned_names[shader] {
			Warn().Printf("Tried to set a uniform in an unknown shader '%s'", shader)
			warned_names[shader] = true
		}
		return
	}
	bvariable := []byte(fmt.Sprintf("%s\x00", variable))
	loc := gl.GetUniformLocation(prog, (*gl.Char)(unsafe.Pointer(&bvariable[0])))
	var fs []gl.Float
	for i := range vs {
		fs = append(fs, gl.Float(vs[i].X))
		fs = append(fs, gl.Float(vs[i].Y))
	}
	gl.Uniform2fv(loc, gl.Sizei(len(vs)), (*gl.Float)(unsafe.Pointer(&fs[0])))
}

func (m *Matrix3) toGLFloat() Matrix3GLFloat {
	var glm Matrix3GLFloat

	for i := range m {
		glm[i] = gl.Float(m[i])
	}

	return glm
}

func drawCells() {

	if input.Zoom > 0 {
		gl.PointSize(gl.Float(float64(Width) / float64(*flagSize) * input.Zoom))
	}

	gl.Color4f(1, 1, 1, 1)
	gl.Enable(gl.POINT_SMOOTH)
	gl.Begin(gl.POINTS)

	for i, j := 0, 0; i < (life.Size * life.Size); i, j = i+life.Size, j+1 {
		for k, v := range life.Cells[i : i+life.Size] {
			if v {
				gl.Vertex2f(gl.Float(k), gl.Float(j))
			}
		}
	}

	gl.End()
	gl.Disable(gl.POINT_SMOOTH)
}