Canvas HUD
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Rendering a basic HUD with a Canvas.
# ==============================================================================
# Head up display
# ==============================================================================
var pow2 = func(x) { return x * x; };
var vec_length = func(x, y) { return math.sqrt(pow2(x) + pow2(y)); };
var round0 = func(x) { return math.abs(x) > 0.01 ? x : 0; };
var HUD = {
canvas_settings: {
"name": "HUD",
"size": [1024, 1024],
"view": [480, 360],
"mipmapping": 1
},
new: func(placement)
{
var m = {
parents: [HUD],
canvas: canvas.new(HUD.canvas_settings),
text_style: {
'font': "LiberationFonts/LiberationMono-Regular.ttf",
'character-size': 18,
'character-aspect-ration': 0.9
}
};
m.canvas.addPlacement(placement);
m.canvas.setColorBackground(0.36, 1, 0.3, 0.02);
m.root = m.canvas.createGroup();
m.root.setScale(1, 1/math.cos(25 * math.pi/180));
m.root.setTranslation(240, 180);
# Heading
m.hdg = m.root.createChild("text");
m.hdg._node.setValues(m.text_style);
m.hdg.setDrawMode(3);
m.hdg.setPadding(2);
m.hdg.setColor(0.36, 1, 0.3);
m.hdg.setColorFill(0.36, 1, 0.3);
m.hdg.setAlignment("center-top");
m.hdg.setTranslation(0, -140);
# Airspeed
m.airspeed = m.root.createChild("text");
m.airspeed._node.setValues(m.text_style);
m.airspeed.setColor(0.36, 1, 0.3);
m.airspeed.setAlignment("right-center");
m.airspeed.setTranslation(-180, 0);
# Groundspeed
m.groundspeed = m.root.createChild("text");
m.groundspeed._node.setValues(m.text_style);
m.groundspeed.setColor(0.36, 1, 0.3);
m.groundspeed.setAlignment("left-center");
m.groundspeed.setTranslation(-220, 90);
# Vertical speed
m.vertical_speed = m.root.createChild("text");
m.vertical_speed._node.setValues(m.text_style);
m.vertical_speed.setColor(0.36, 1, 0.3);
m.vertical_speed.setFontSize(10, 0.9);
m.vertical_speed.setAlignment("right-center");
m.vertical_speed.setTranslation(205, 50);
# Radar altidude
m.rad_alt = m.root.createChild("text");
m.rad_alt._node.setValues(m.text_style);
m.rad_alt.setColor(0.36, 1, 0.3);
m.rad_alt.setAlignment("right-center");
m.rad_alt.setTranslation(220, 70);
# Waterline / Pitch indicator
m.root.createChild("path")
.moveTo(-24, 0)
.horizTo(-8)
.lineTo(-4, 6)
.lineTo(0, 0)
.lineTo(4, 6)
.lineTo(8, 0)
.horizTo(24)
.setStrokeLineWidth(0.9)
.setColor(0.36, 1, 0.3, 0.8);
# Flightpath/Velocity vector
m.vec_vel =
m.root.createChild("path")
.moveTo(8, 0)
.arcSmallCCW(8, 8, 0, -16, 0)
.arcSmallCCW(8, 8, 0, 16, 0)
.close()
.moveTo(-8, 0)
.horiz(-16)
.moveTo(8, 0)
.horiz(16)
.setStrokeLineWidth(0.9)
.setColor(0.36, 1, 0.3, 0.8);
# Horizon
m.horizon_group = m.root.createChild("group");
m.h_trans = m.horizon_group.createTransform();
m.h_rot = m.horizon_group.createTransform();
for(var i = 5; i <= 10; i += 5)
m.horizon_group.createChild("path")
.moveTo(24, -i * 18)
.horiz(48)
.vert(7)
.moveTo(-24, -i * 18)
.horiz(-48)
.vert(7)
.setStrokeLineWidth(1.5)
.setColor(0,1,0, 0.65);
# Horizon line
m.horizon =
m.horizon_group.createChild("path")
.moveTo(-500, 0)
.horizTo(500)
.setStrokeLineWidth(1.5)
.setColor(0,1,0, 0.65);
m.input = {
pitch: "/orientation/pitch-deg",
roll: "/orientation/roll-deg",
hdg: "/orientation/heading-deg",
speed_n: "velocities/speed-north-fps",
speed_e: "velocities/speed-east-fps",
speed_d: "velocities/speed-down-fps",
alpha: "/orientation/alpha-deg",
beta: "/orientation/side-slip-deg",
ias: "/velocities/airspeed-kt",
gs: "/velocities/groundspeed-kt",
vs: "/velocities/vertical-speed-fps",
rad_alt: "/instrumentation/radar-altimeter/radar-altitude-ft",
wow_nlg: "/gear/gear[4]/wow"
};
foreach(var name; keys(m.input))
m.input[name] = props.globals.getNode(m.input[name], 1);
return m;
},
update: func()
{
me.airspeed.setText(sprintf("%d", me.input.ias.getValue()));
me.groundspeed.setText(sprintf("G %3d", me.input.gs.getValue()));
me.vertical_speed.setText(sprintf("%.1f", me.input.vs.getValue() * 60.0 / 1000));
var rad_alt = me.input.rad_alt.getValue();
if( rad_alt and rad_alt < 5000 ) # Only show below 5000AGL
rad_alt = sprintf("R %4d", rad_alt);
else
rad_alt = nil;
me.rad_alt.setText(rad_alt);
me.hdg.setText(sprintf("%03d", me.input.hdg.getValue()));
me.h_trans.setTranslation(0, 18 * me.input.pitch.getValue());
var rot = -me.input.roll.getValue() * math.pi / 180.0;
me.h_rot.setRotation(rot);
# flight path vector (FPV)
var vel_gx = me.input.speed_n.getValue();
var vel_gy = me.input.speed_e.getValue();
var vel_gz = me.input.speed_d.getValue();
var yaw = me.input.hdg.getValue() * math.pi / 180.0;
var roll = me.input.roll.getValue() * math.pi / 180.0;
var pitch = me.input.pitch.getValue() * math.pi / 180.0;
var sy = math.sin(yaw); var cy = math.cos(yaw);
var sr = math.sin(roll); var cr = math.cos(roll);
var sp = math.sin(pitch); var cp = math.cos(pitch);
var vel_bx = vel_gx * cy * cp
+ vel_gy * sy * cp
+ vel_gz * -sp;
var vel_by = vel_gx * (cy * sp * sr - sy * cr)
+ vel_gy * (sy * sp * sr + cy * cr)
+ vel_gz * cp * sr;
var vel_bz = vel_gx * (cy * sp * cr + sy * sr)
+ vel_gy * (sy * sp * cr - cy * sr)
+ vel_gz * cp * cr;
var dir_y = math.atan2(round0(vel_bz), math.max(vel_bx, 0.01)) * 180.0 / math.pi;
var dir_x = math.atan2(round0(vel_by), math.max(vel_bx, 0.01)) * 180.0 / math.pi;
me.vec_vel.setTranslation(dir_x * 18, dir_y * 18);
settimer(func me.update(), 0);
}
};
var init = setlistener("/sim/signals/fdm-initialized", func() {
removelistener(init); # only call once
var hud_pilot = HUD.new({"node": "HUD.l.canvas"});
hud_pilot.update();
# var hud_copilot = HUD.new({"node": "HUD.l.canvas.001"});
# hud_copilot.update();
});