func DrawLine(start, end vect.Vect) {
gl.Begin(gl.LINES)
defer gl.End()
gl.Vertex2d(start.X, start.Y)
gl.Vertex2d(end.X, end.Y)
}
func DrawQuad(upperLeft, lowerRight vect.Vect, filled bool) {
if filled {
gl.Begin(gl.QUADS)
} else {
gl.Begin(gl.LINE_LOOP)
}
defer gl.End()
gl.Vertex2d(upperLeft.X, upperLeft.Y)
gl.Vertex2d(upperLeft.X, lowerRight.Y)
gl.Vertex2d(lowerRight.X, lowerRight.Y)
gl.Vertex2d(lowerRight.X, upperLeft.Y)
}
func DrawPoly(vertices []vect.Vect, vertCount int, filled bool) {
if filled {
gl.Begin(gl.TRIANGLE_FAN)
gl.Vertex2d(vertices[0].X, vertices[0].Y)
} else {
gl.Begin(gl.LINE_LOOP)
}
defer gl.End()
for i := 0; i < vertCount; i++ {
v := vertices[i]
gl.Vertex2d(v.X, v.Y)
}
}
func DrawCircle(pos vect.Vect, radius float64, filled bool) {
if filled {
gl.Begin(gl.TRIANGLE_FAN)
gl.Vertex2d(pos.X, pos.Y)
} else {
gl.Begin(gl.LINE_LOOP)
}
defer gl.End()
var d float64
for i := 0.0; i <= 360; i += circlestep {
d = deg2grad * i
gl.Vertex2d(pos.X+math.Cos(d)*radius, pos.Y+math.Sin(d)*radius)
}
}