Projector and display control method for projector with orientation correction

A projector that projects an image, comprising:

• a light source;
• a light modulation device that modulates light output from the light source and forms an image in response to input image data;
• a projection optical device that projects the image formed by the light modulation device;
• a control device that controls the light modulation device;
• and
• a position detection device that detects a projection position of the projector as one of a vertical projection position for projection of the image on a vertical surface and a horizontal projection position for projection of the image on a horizontal surface,
• wherein the control device includes
• a determination unit that determines whether the projection position detected by the position detection device is a predetermined position, and
• a correction unit that corrects an orientation of the image data so that a longer side of the image data coincides with a longer side of an image formation area of the light modulation device if the determination unit determines that the detected projection position is the predetermined position.