3D Projections Perspective and Parallel Projections Parallel Projections Orthographic and Oblique Isometric View Oblique Projections Contents 3D ID: 530558
Download Presentation The PPT/PDF document "3D Projection Transformations" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
3D Projection TransformationsSlide2
3D Projections
-Perspective and Parallel ProjectionsParallel Projections: -Orthographic and Oblique -Isometric ViewOblique Projections
ContentsSlide3
3D
Projections3D projection is any method of mapping three-dimensional points to a two-dimensional plane.PerspectiveParallelOrthographic
Oblique
Elevations
Axonometric
Isometric
Cava
l
ier
Cabinet
Rays parallel to view plane
Rays converge on eye position
BACKSlide4
Perspective and Parallel Projections
View plane
Perspective
Rays converge on eye position
Parallel
Rays parallel to view plane
BACK
When the human eye views a scene, objects in the distance appear smaller than objects close by - this is known as
perspe
ctive
. Slide5
3D Projections
PerspectiveParallelOrthographicOblique
Elevations
Axonometric
Isometric
Cavalier
Cabinet
Rays parallel
Rays converge on eye position
Rays perpendicular to view plane
Rays at an angle to view plane
BACKSlide6
Parallel
Projections:Orthographic and ObliqueView plane
Orthographic
Rays perpendicular to view plane
Oblique
Rays at an angle to view plane
BACKSlide7
3D Projections
PerspectiveParallelOrthographicOblique
Elevations
Axonometric
Isometric
Cavalier
Cabinet
Rays parallel
Rays converge on eye position
Rays perpendicular to view plane
Rays at angle to view plane
View plane aligned with principal axes
View plane not aligned with principal axes
Dimetric
Trimetric
BACKSlide8
Isometric View
In isometric view, the three principal axes of the object intersect the view plane at equal distance. Therefore, when projected, they are 120o apart.BACKSlide9
3D Projections
PerspectiveParallelOrthographicOblique
Elevations
Axonometric
Isometric
Cavalier
Cabinet
Rays parallel
Rays converge on eye position
Rays perpendicular to view plane
Rays at angle to view plane
BACKSlide10
Oblique projections
Projection lines are at an angle to the view plane i.e. Projection lines are not perpendicular to view plane.Cavalier :Here direction of projection makes 45 degrees angle with view plane and the projection of a line perpendicular to view plane has same length as the line.
a
1
1
1
1
a
1
1/2
2
1
BACK
Cabinet
:Here
direction of projection makes 63.4 degrees angle with view plane and the projection and lines perpendicular to viewing surface are projected at one half their actual length.Slide11
Thanks !!!