questions about graphics

How to create a paint app for iPhone?

I would like to develop a MS paint like app for the iPhone. Could you guys point me to some sample or tutorials on this topic? I'm new to Objective C and Xcode. Thanks ...

iphone

graphics

tutorials

rotate a plane around a diagonal

I would like to rotate a plane, not around a single (X or Y) axis, but around the diagonal (45 degrees between X and Y). How do I calculate the Rx and Ry given the Rdiagonal? (Rdiagonal is the amount of rotation I would like to achieve around the diagonal axis). To clarify: just take a yellow PostIt and draw cross on it (a horizonal an...

graphics

linear-algebra

How do I draw a proper parallelogram that can be animated on iPhone?

I'm trying to do something very simple: I need some parallelograms in my program. These are attached to other objects, all of which are UIViews. It's important that I be able to animate these, since the objects they are attached to can also be animated. I've figured out how to use the transform in UIView/CALayer to do this, but the prob...

How do you draw a line from one corner of the stage to the other?

I am completely perplexed. I asked this question and it (any mentioned solution) doesn't seem to be working at all. All I want is to draw a line from one corner to the other. Here again is the link to the SWF file I have (it's embedded in an HTML document): test.html Here is the source: package { import flash.display.Sprite; ...

Inset selection in gimp? Reverse drop-shadow?

I'm wondering how to achieve this effect that Apple uses. It looks as though the button is depressed into the bar, can't figure out how to do the same effect for my graphics. Thanks! ...

In cocos2d, what is the method to change the anchorPoint and position without causing it to suddenly jump?

In cocos2d, I have a CCLayer that is being moved and scaled using touches and pinch gestures. By default, the zoom always goes towards the anchorPoint. Changing the anchorPoint fixes my zoom problem, but causes the sprite to suddenly jump. Here are two similar questions here and here, but I still don't know exactly what to do. Than...

.NET Graphics.ScaleTransform converts print job to bitmap. Any other way to scale text?

I'm using Graphics.ScaleTransform to stretch lines of text so they fit the width of the page, and then printing that page. However, this converts the print job to a bitmap - for a print with many pages this causes the size of the print job to rise to obscene proportions, and slows down printing immensely. If I don't scale like this, the...

What's a good matrix manipulation library available for C ?

Hi, I am doing a lot of image processing in C and I need a good, reasonably lightweight, and above all FAST matrix manipulation library with a permissive license. I am mostly focussing on affine transformations and matrix inversions, so i do not need anything too sophisticated or bloated. Primarily I would like something that is very f...

X (close) shape in SVG

I'm trying to make this SVG shape (ignore the color background, just the X shape) Close SVG Path but don't have Illustrator and wouldn't know how to use it. Can someone help out with the general idea, or point me to alternatives. I'm using it in flex. ...

Graphics/Vision Interesting Topics

Hello: I would like to do an interesting project for a computer graphics course. I know that there is a lot of literature out there (i.e. SIGGRAPH conference papers). I have a very large range of interest with regard to computer graphics (i.e. image processing, 3D modeling, rendering, animation). However, I've only taken computer vision...

windows: include native window output in a custom render pipeline

Hi all, I am working on windows port of xbmc. I am trying to integrate chromium browser into xbmc using chromiumembedded framework. Xbmc has its own rendering framework and ideal solution would be to get rgb data from cromium window and render it using xbmc functions. That would allow us to create webbrowser gui conrol. Chromiumembedde...

GDI: Dynamical Multiple Graphics in a page?

Hi all, I'm quite new to drawing shapes, graphics, bitmaps etc. I googled for a few days,but still havent got a real clue what to do, so please help me: I want to draw a floorplan with certain objects(represented as circles) moving on it. When I click on a object, it needs to show something. So far, I ve been able to draw some circles ...

Video Synthesis - Making waves, patterns, gradients...

I'm writing a program to generate some wild visuals. So far I can paint each pixel with a random blue value: for (y = 0; y < YMAX; y++) { for (x = 0; x < XMAX; x++) { b = rand() % 255; setPixelColor(x,y,r,g,b); } } I'd like to do more than just make blue noise, but I'm not sure where to start (Google isn't help...

Clear Graphics Object to Black or other RGB

I am a rank beginner in C#. I am currently using this code: objGraphics.Clear(SystemColors.Control); What I want to do is Clear this object to black (or some other RGB color), and I'm stumped as to how to replace the SystemColors.Control with, preferably, an RGB color spec. I'd probably want to clear to black most of the tim...

c#

graphics

Lighting does not work with gluSphere

This is a simple issue that I'm somewhat ashamed to ask for help on. I'm making a simple call to gluSphere to render a sphere, however, it does not light properly even though I'm pretty sure I added the normals and lighting correctly. If, however, I add a texture, the model lights normally, except it seems to be always SMOOTH, and I can...

opengl

graphics

jogl

Convert text box text into Argb argument

I have been looking into coloring objects like ellipses with code such as SolidBrush trnsRedBrush = new SolidBrush(Color.FromArgb(0x78FF0000)); I'd like to play around further with this by entering FromArgb's argument into a textbox on a form, then using the textbox to set the Brush's color. How would I convert the textbox's...

c#

graphics

How do I use texture-mapping in a simple ray tracer?

I am attempting to add features to a ray tracer in C++. Namely, I am trying to add texture mapping to the spheres. For simplicity, I am using an array to store the texture data. I obtained the texture data by using a hex editor and copying the correct byte values into an array in my code. This was just for my testing purposes. When the v...

c++

graphics

texture-mapping

WinForms / .Net interactive world map - how?

In a CD collection program, I have each artist's country of origin stored in the main database and want to display a map of the world which: Colour-codes each country depending on the number of CDs by artists in that country Allows clicking on each country to filter a list of CDs to only ones by artists in that country This is a heav...