Upcoming SlideShare
×

# Graphic expression

476 views

Published on

3 Likes
Statistics
Notes
• Full Name
Comment goes here.

Are you sure you want to Yes No
• Be the first to comment

Views
Total views
476
On SlideShare
0
From Embeds
0
Number of Embeds
1
Actions
Shares
0
6
0
Likes
3
Embeds 0
No embeds

No notes for slide

### Graphic expression

1. 1. GRAPHIC EXPRESSION Lesson 2. 1st term
2. 2. Perspective in drawings • We use projection drawings to represent 3D objects in two dimensions (our paper) • There are two types of projections: Cylindrical (Orthogonal) Conic •No distorsion •Vanishing point (VP) far away •Objects are distorted in the same way our eyes see them •Vanishing point close (x, y, z) VP VP
3. 3. First angle projection • Cylindrical projection composed of three views (taken from very far away) of the object: front side top
4. 4. First angle projection: result front top side
5. 5. Oblique projection • We represent one of the faces (mathing with X and Y axis) in true dimension and the others are distorted. Y Z X
6. 6. Representing objects in oblique projection We have to consider the X, Y and Z axis. We first draw the front face of the figure (X and Y axis Then we draw the sides corresponding with the z axis with a reduction coefficient of 1/2 We finally close the figure with the lines corresponding to the back of the figure Y Z X
7. 7. Axonometric projection _ Isometric projection • Axonometric projection shows an object from the corner so we see its three sides • Objects seem distorted because the same scale is used for all features • One axis is drawn vertical and the others are at an angle. 120º 120º 120º Isometric projection
8. 8. Drawing objects in isometric projection We draw according the axis at 120º angles We first draw a figure’s corner 120º 120º 120º Second we draw the lines which correspond to the sides next to the corner, corresponding with Z axis Then we draw the lines corresponding to the left and rigth corners We first draw a figure’s corner Isometric projection
9. 9. Two point perspective Draw an horizontal line across the page and mark two vanishing points: VP1 and VP2  Draw one corner of the box: vertical line Draw the construction lines from the top and the botton of the corner to the vanishing point  Draw two vertical lines corresponding to the left and rigth corners. They go from the top to the botton lines Draw the last construction lines from the top and the botton of the other corners Complete the box using the construction lines VP1 VP 2
10. 10. Single point perspective First draw the front of the cube. Then add a vanishing point (X) Draw thin construction lines from each corner to the vanishing point Draw the lines which correspond to the back of the figure Draw the rest of the figure over the segments of the construction lines VP
11. 11. Dimensioning • To dimension means “to indicate the real size of an object in its drawing” 70 25 50 45
12. 12. Scale
13. 13. Magnitudes and units • Magnitude is a physical property which we can measure / determine / quantify: i.e: length, mass,… • Units are the symbols which go after a number and identify the magnitude we refer to
14. 14. Types of magnitudes • Fundamental: we can express or determine them with a direct measurement: there are seven: mass (M), length (L), time (t) • Derived (derivadas): they are obtained by combining the fundamental magnitudes: force, volume, surface…