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Tinging an image

An image can be tinged with a color and its transparency can be set by assigning a given value to the alpha channel. Forthis purpose, the function tint() can be used. For example, a blue tone can be assigned to the inlaidimage of [link] by just preceding the second image() command with tint(0, 153, 204, 126) .

Translations, rotations, and scale transformations

Representing points and vectors

In computer graphics, points and vectors are represented with the
homogeneous coordinates
quadruples of numbers, where the first triple is to be read in the X-Y-Z space, while thefourth number indicates a vector if it takes value 0, or a point if it takes value 1.
A translation is obtained by adding, in homogeneous coordinates, a vector to a point, and the result is apoint. Alternatively we ca see a translation as a matrix-vector product (see Matrix Arithmetic ), where the matrix is 1 0 0 t x 0 1 0 t y 0 0 1 t z 0 0 0 1 , and the vector is the one representing the point x y z 1 . An anti-clockwise rotation by the angle θ around the axis z ( roll ), is obtained by the rotation matrix θ θ 0 0 θ θ 0 0 0 0 1 0 0 0 0 1 . Rotations around the axes x ( pitch ) and y ( yaw ) are realized by means of rotation matrices of the same kind, anda rotation around an arbitrary axis can be obtained by composition (left multiply) of elementary rotations aroundeach of the main axes.

Translations

The function translate() moves an object in the image window. It takes two or three parameters, being thedisplacements along the directions x , y (and z ), respectively.

Rotations

In two dimensions, the function rotate() is used to rotate objects in the image window. This is obtained by (left) multiplying thecoordinates of each pixel of the object by a rotation matrix. Rotations are always specified around the top leftcorner of the window (
    0 0
coordinate). Translations can be used to move the rotation axis to other points. Rotation angles are specifiedin radians. Recall that 2 rad 360 ˚ . For example, insert the rotation rotate(PI/3) before the second image() command in [link] . In three dimensions, we can use elementary rotations around the coordinate axes rotateX() , rotateY() , e rotateZ() .

Scale transformations

The function scale() allows to expand or contract an object by multiplication of its point coordinates by a constant. When itis invoked with two or three parameters, different scalings can be applied to the three axes.

Typographic elements

Every tool or language for media manipulation gives the opportunity towork with written words and with their fundamental visual elements: typographic characters.

The aspect of a type has two main components: font and size.

Processing has the class PFont and the methods loadFont() (to load a font and assign it to an object of the PFont class) and textFont() (to activate a font with a specific size). In order to load afont, this has to be pre-loaded into the directory data of the current sketch. The tool Create Font , accessible from the Tools menu in Processing, creates the bitmaps of the characters that theprogrammer intends to use. The file with the bitmaps is put in the data directory. After these preliminary operations, the font can be used to write some text, using thefunction text() . With this function, a string of characters can be put in the 2D or 3D space, possiblyinserting it within a rectangular box. The alignment of characters in the box is governed by the function textAlign() . In the default configuration, the written text can be spatially transformed like any otherobject. The color of characters can be set with the usual fill() , like for any other graphic object.

Questions & Answers

A golfer on a fairway is 70 m away from the green, which sits below the level of the fairway by 20 m. If the golfer hits the ball at an angle of 40° with an initial speed of 20 m/s, how close to the green does she come?
Aislinn Reply
cm
tijani
what is titration
John Reply
what is physics
Siyaka Reply
A mouse of mass 200 g falls 100 m down a vertical mine shaft and lands at the bottom with a speed of 8.0 m/s. During its fall, how much work is done on the mouse by air resistance
Jude Reply
Can you compute that for me. Ty
Jude
what is the dimension formula of energy?
David Reply
what is viscosity?
David
what is inorganic
emma Reply
what is chemistry
Youesf Reply
what is inorganic
emma
Chemistry is a branch of science that deals with the study of matter,it composition,it structure and the changes it undergoes
Adjei
please, I'm a physics student and I need help in physics
Adjanou
chemistry could also be understood like the sexual attraction/repulsion of the male and female elements. the reaction varies depending on the energy differences of each given gender. + masculine -female.
Pedro
A ball is thrown straight up.it passes a 2.0m high window 7.50 m off the ground on it path up and takes 1.30 s to go past the window.what was the ball initial velocity
Krampah Reply
2. A sled plus passenger with total mass 50 kg is pulled 20 m across the snow (0.20) at constant velocity by a force directed 25° above the horizontal. Calculate (a) the work of the applied force, (b) the work of friction, and (c) the total work.
Sahid Reply
you have been hired as an espert witness in a court case involving an automobile accident. the accident involved car A of mass 1500kg which crashed into stationary car B of mass 1100kg. the driver of car A applied his brakes 15 m before he skidded and crashed into car B. after the collision, car A s
Samuel Reply
can someone explain to me, an ignorant high school student, why the trend of the graph doesn't follow the fact that the higher frequency a sound wave is, the more power it is, hence, making me think the phons output would follow this general trend?
Joseph Reply
Nevermind i just realied that the graph is the phons output for a person with normal hearing and not just the phons output of the sound waves power, I should read the entire thing next time
Joseph
Follow up question, does anyone know where I can find a graph that accuretly depicts the actual relative "power" output of sound over its frequency instead of just humans hearing
Joseph
"Generation of electrical energy from sound energy | IEEE Conference Publication | IEEE Xplore" ***ieeexplore.ieee.org/document/7150687?reload=true
Ryan
what's motion
Maurice Reply
what are the types of wave
Maurice
answer
Magreth
progressive wave
Magreth
hello friend how are you
Muhammad Reply
fine, how about you?
Mohammed
hi
Mujahid
A string is 3.00 m long with a mass of 5.00 g. The string is held taut with a tension of 500.00 N applied to the string. A pulse is sent down the string. How long does it take the pulse to travel the 3.00 m of the string?
yasuo Reply
Who can show me the full solution in this problem?
Reofrir Reply
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Source:  OpenStax, Media processing in processing. OpenStax CNX. Nov 10, 2010 Download for free at http://cnx.org/content/col10268/1.14
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