// draw the bar and the arrow
private void DrawVBar(SpriteBatch batch, ButtonSprite btn,
float value, float min)
{
// determine the X of the arrow
// NOTE: btn.RectNormal describes the bounds of the image
// btn.RectPressed describes the bounds of the bar itself
m_btnVBarArrow.Location.X =
btn.Location.X +
btn.RectPressed.X +
btn.RectPressed.Width / 2 -
m_btnVBarArrow.RectNormal.Width / 2;
if (min < 0.0f)
{
// value is between -1.0f and 1.0f. offset value
// so that value is between 0.0f and 2.0f
value += 1.0f;
// then scale so that so that value is
// between 0.0f and 1.0f
value /= 2.0f;
}
// since value is now between 0 and 1, we can treat it
// like a percentage. so, Y becomes value percent of
// Height. NOTE: need to invert value since Y values
// increase as you move down the screen. (see line with
// "// bottommost" comment)
m_btnVBarArrow.Location.Y =
btn.Location.Y + btn.RectPressed.Y + // topmost pixel
btn.RectPressed.Height - // bottommost
btn.RectPressed.Height * value - // scaled value
m_btnVBarArrow.RectNormal.Height / 2; // arrow midpoint
// draw bar
batch.Draw(btn.TextureNormal, btn.Location,
btn.RectNormal, Color.White);
// draw arrow
DrawButton(batch, m_btnVBarArrow, false);
}
// overload for DrawVBar, with default min
private void DrawVBar(SpriteBatch batch, ButtonSprite btn,
float value)
{
DrawVBar(batch, btn, value, -1.0f);
}
// draw the bar and the arrow
private void DrawHBar(SpriteBatch batch, ButtonSprite btn, float value, float min)
{
// determine the Y of the arrow
// NOTE: btn.RectNormal describes the bounds of the image
// btn.RectPressed describes the bounds of the bar itself
m_btnHBarArrow.Location.Y =
btn.Location.Y + btn.RectPressed.Y +
btn.RectPressed.Height / 2 -
m_btnHBarArrow.RectNormal.Height / 2;
if (min < 0.0f)
{
// value is between -1.0f and 1.0f. offset value
// so that value is between 0.0f and 2.0f
value += 1.0f;
// then scale so that so that value is
// between 0.0f and 1.0f
value /= 2.0f;
}
// since value is now between 0 and 1, we can treat it
// like a percentage. so, X becomes value percent of
// Height.
m_btnHBarArrow.Location.X =
btn.Location.X + btn.RectPressed.X + // leftmost pixel
btn.RectPressed.Width * value - // scaled value
m_btnHBarArrow.RectNormal.Width / 2; // arrow midpoint
// draw bar
batch.Draw(btn.TextureNormal, btn.Location,
btn.RectNormal, Color.White);
// draw arrow
DrawButton(batch, m_btnHBarArrow, false);
}
// draw the active port indicators
private void DrawPort(SpriteBatch batch, ButtonSprite btn, int index, bool active)
{
// gray (inactive) or green (active) circle
DrawButton(batch, btn, active);
// port number
batch.Draw(btn.TextureNormal, btn.Location, m_rectPortNum[index], Color.White);
}
// draw the button at its current location in its current state
private void DrawButton(SpriteBatch batch, ButtonSprite btn,
bool pressed)
{
if (pressed)
{
batch.Draw(btn.TexturePressed, btn.Location,
btn.RectPressed, Color.White);
}
else
{
batch.Draw(btn.TextureNormal, btn.Location,
btn.RectNormal, Color.White);
}
}