Texture mapping apparatus

DETAILED DESCRIPTION It is an object of the present invention to provide a texture mapping apparatus capable of accurately mapping a texture original figure at a high speed.
It is another object of the invention to provide a texture mapping apparatus capable of accurately mapping a texture original figure at a high speed even though a polygon presents a butterfly plane.
It is a further object of the invention to provide a texture mapping apparatus capable of mapping a texture original figure without the use of an additional memory.
In order to achieve the objects above-mentioned, the texture mapping apparatus in accordance with the present invention comprises first and second side detector means, first and second side interpolation means, first and second line segment interpolation means and a mapping memory.
The first side detector means is adapted to detect two opposite sides of a Polygon having a unit area at a display side which constitutes a desired area on a display plane.
The second side detector means is adpated to detect two sides of a polygon having a unit area at a texture side which constitutes a desired area on a texture plane, the two sides corresponding to the first-mentioned two opposite sides at the display side.
The first side interpolation means is adapted to linearly interpolate the opposite sides of a unit area polygon at the display side, while the second side interpolation means is adapted to linearly interpolate two sides of a unit area polygon at the texture side.
Interpolation data supplied from the first side interpolation means are entered into the first line segment interpolation means, while interpolation data supplied from the second side interpolation means are entered into the second line segment interpolation means.
The second line segment interpolation means is adapted to carry out an interpolation operation in synchronism with the first line segment interpolation means.
Address data supplied from the second line segment interpolation means are entered into the mapping memory, from which address data corresponding to the address data thus entered are read out