Performance: optimize car drawing by not recreating dynamic sprite each time when angle changes

[ivan-mogilko]

Here how it looks now:

ags-lastfurious/Last'n'Furious/VehicleBase.asc

Lines 88 to 107 in bc40d46

	// TODO: perhaps cache a number of often-used angles to improve perfomance?
	if (this.dSprite == null || angle != this.dSpriteRotation) {
	if (this.dSprite != null)
	this.dSprite.Delete();
	if (angle != 0) {
	DynamicSprite *spr = DynamicSprite.CreateFromExistingSprite(this.carSprite, true);
	spr.Rotate(angle);
	this.dSprite = spr;
	this.viewFrame.Graphic = this.dSprite.Graphic;
	// HACK: poke AGS to refresh the character cache
	DrawingSurface *ds = this.dSprite.GetDrawingSurface();
	ds.DrawPixel(-1, -1);
	ds.Release();
	} else {
	this.dSprite = null;
	this.viewFrame.Graphic = this.carSprite;
	}
	this.dSpriteRotation = angle;
	}

The problem was that AGS does not provide some kind of "DrawRotated" function, so you have to rotate existing sprite.
Might try this: create a max-sized square sprite and keep drawing on it with necessary offsets; then also use same offsets when locking character's view.

Also if you do that, there will be no need to "poke" the engine by putting a single pixel.