# Tag Info

33

Digital colors can be made up of three components: red, green, and blue. Combine these together, and you get final color, eg. yellow is 100% red, 100% green and 0% blue. The fourth component is, as you mentioned, transparency. Together, these form the tuple RGBA (red, green, blue, alpha) which represent an image. Now, instead of pixels, think about it ...

6

The term comes from the definition of "channel" that means a specific portion of a frequency spectrum. In this case, the red, green and blue components of a color are often referred to as "channels" (since red, green and blue light are portions of the visible light spectrum). Since alpha is another component of color in computer graphics (although not one ...

4

I will assume that you have a function f such that the surface is defined by f(x,y,z)==0. Right now, all you have is the function f itself, and so with no further information, it is impossible to know when to subdivide. It is always possible for the surface to do what you describe, i.e. the function f can have arbitrarily thin "fins" which can require you do ...

4

Alpha channels were actually invented by George Lucas's company Industrial Light & Magic (actually Alvy Ray Smith did most of the work while working there, who was previously employed by Xerox PARC - who we can thank for almost everything in modern computing!). Alpha channels, in addition to doing cool effects like transparent window, transparent ...

3

None of the other examples explain why it's alpha, though. It's from the expression in Alpha Compositing: where Ca and Cb are the two input colour values and Co is the output combined colour. Varying the alpha between 0 and 1 varies the colour between front and back composited images. (Image processing also has "gamma", but not "beta" as far as I know)

3

In many image format, A pixel is defined as a vector with 4 components. RGB and alpha. In the perspective of whole image, you can select only each component of the pixel, and this provides a series of values. If you want to process only one component, then you can select the comonent of all the pixels of the image, and this is usually called a channel. A ...

3

All images have 1 or more "channels" of information. For example, the familiar RGB image type has 3 channels of information: Red, Green, and Blue. That is, every pixel in the image has 3 numbers associated with it (if each number is 8 bits, then that's a 24 bit image). Alpha can add a 4th channel of information (so a 4th number associated with each pixel, ...

3

Use floating point variables for entities' velocity and position. Use integers only when translating from world position to screen position. This way, your ship will move smoothly thorugh tiles. Also, add a Camera object to convert your world coordinates to screen coordinates as soon as possible.

2

in your Tile.render function you are multiplying the coordinates with the (half) width and height of the current image. But keep in mind that the grid-size of your world is fixed to the size of a normal tile. When you move an object 2 units to the left, its own size is irrelevant. Only the size of the unit matters. Calculate the position based on the size ...

2

No, your way of doing it is exactly how AABB collisions work, being the most basic rectangle to rectangle collision: http://www.opentk.com/node/869. You basically check if any of the sides of a given rectangle are too far from those of a second one. As you can see here, as soon as a side is too far, the rectangles don't collide. You would need to take ...

2

In addition to bogglez answer (you don't need to re-render shadow maps which haven't changed between frames), there is also the possibility to render several lights at once if each light has its own shadow map. This is more of an issue with a forward (i.e. non-deferred) renderer where you want to avoid churning through all the geometry in your scene for each ...

2

In the first solution you can keep the shadow map if nothing changed, in the second solution you always need to re-render the shadow map. That makes the first solution better for scenes which are somwhat static.

2

On of the major reason your code is slow is because you load your bitmap every time you render your game. Try putting this line in an initialization function: ... Bitmap bitmap; protected void init() { bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.menu_bg); } ... protected void onDraw() { //Set Rectangle Size and Coordinates ...

1

I posted recently a response to a similar question http://stackoverflow.com/questions/24231389/struct-or-class-for-matrix-4x4-object Basically valuetypes are the way to go for storing matrices, more benefits than downsides. You may also organize a matrix to be more GPU friendly by transposing the fields directly into the matrix struct (SharpDX is not doing ...

1

A pixel is a collection of components. Traditionally these components are red, green and blue, with each of them taking 8 bits of data. As it is often advantageous to have memory aligned certain ways, these where sometimes packed into 32 bits of space each. This leaves 8 bits of extra data at the end of each pixel. As this is neither red, nor green, or ...

1

The strategy we will follow is bounding the derivative, as the technique of splitting the query regions is very complex and probably very slow. Consider first a 1D function f, for which everywhere, |f'| < 0.3. We are given that f(3)=-2. What is a bound for f over the interval [1, 5]? Looking at the derivative bound, we have: | df | | -- | < 0.3 | dx | ...

1

"Real-time rendering" is calculated at the instant you ask for your whatever solution to generate the images (different technologies are used to achieve this target). "Off-line" rendering is not necessarily the contrary of "real-time". The term is often used when speaking about configurators and especially web-configurators. Sometimes people also use the ...

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