Category Archives: Demos

Executables created to show programming skills or the power of some hardware feature, operative system, programming language, library and so on.

Super Mario Bros for Amstrad CPC 464

When i was a little kid I remember that i really wanted to create a Super Mario Bros game for the amstrad cpc 464. Now that I am 33 and I work as a software engineer I asked myself: why don't you make your old dream come true? :) Finally I found the time to create a demo with the famous first Level 1-1 of Super Mario Bro:

The horizontal hardware scrolling needs a double buffer in order to get an accuracy of 4 pixels. The demo runs on original Amstrad CPC 464 speed emulated by Caprice. It is pretty fast and can loop horizontally with a limit of 512 tiles meanwhile the level 1-1 takes only 212 tiles. I readjusted the original smb graphics to fit a 256x192 Mode 1 with 4 colors. I really like the effect of the gray scale map mixed with the blue sky, like in the original NES game. This demo has been programmed with SDCC in C and Z80 assembly.

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Unrelated Engine – Aquarium 3D

Aquarium 3D is a little demo of an engine that I'm developing for my framework. It uses a multithreading system with a thread for the physic engine and a thread that draws the graphics on the screen: the two threads are perfectly synchronized to maintain the best fluidity possible with different framerates.

The physic engine has a static number of iterations per second, in this case 30. It can obtain a good fluidity of movements also on higher fps of the graphics card (like 75 for example) upscaling the static framerate with a series of trajectory corrections. It uses also OpenGL for graphics,GLUT to open the window and lib3ds to import the 3d studio meshes. The fish models are property of this site:

Gianpaolo Ingegneri
Copyright @ 2010 – All right reserved

Ultra Fast Interpolation (via software)

In general, interpolation is a method used to construct a range of values from a set of data points. In digital image computing there are several methods of interpolation to improve the aspect of a transformed image but there is a problem: all of them are too slow to work via software in real time. Infact, we can see fast interpolations in 3d games only because they are performed via hardware by the graphic card (infact in the past it was very difficult to see an interpolation performed in real time).  However, interpolation is usefull  not only for 3d engines but they are an important part of digital image computing so there is a real need to develop a method to make it faster, expecially if you have to work with a large amount of images at the same time. For this reason I have programmed from scratch a set of  optimized algorithms of interpolation that are definite as in the past... but 100 times faster! The only limitation is that they can be used only for scale trasform but numerically they are perfect and faster at the same time.


Moreover, they are useful to generate procedural images in real time, like textures, that can be used in 3d engine or in some paint softwares where you cannot have a 3d card to speed up all the stuff. In this demo you can see the high performaces of different algorithms with images of 16 bit per pixel. To make sure that my interpolation is numerically perfect, I have included also the calculus of the normal map and the bump mapping effect. With biquadratic interpolation you will obtain a still perfect scaled bump map because the normal map calculus is derivative and the biquadratic is a second order reconstruction filter.

There are the performances on my computer:

Zoom 1x (on a 512x512 image)

- Nearest: 400 fps - Bilinear: 270 fps - Biquadratic: 80 fps

Zoom 4x (on a 512x512 image)

- Nearest: 965 fps - Bilinear: 780 fps - Biquadratic: 245 fps

Zoom 16x (on a 512x512 image)

- Nearest: 1405 fps - Bilinear: 1165 fps - Biquadratic: 390 fps

As you can see, the speed of the algorithm is directly proportional to the size of the zoom, however it is very fast also at the minimum size of 1x. This condition is very useful if you have to resize images or to generate textures with a large amount of stretched layers, like perlin noise. CPU: Intel 2 QuadCore 2333 Mhz; RAM: 4 GB DDRII 800Mhz

Gianpaolo Ingegneri
Copyright @ 2010 – All right reserved

Texture Generation V1.0

This time it was a little bit harder. As you can see in this video, my engine can generate in real time very complex textures with the maximum detail at the maximum speed possible.

Each texture is generated in real time at the frame rate showed on the top-left corner of the window (the "generation" label).

- Lumps (512x512, 200 objs, 16 bpp, 345 FPS)
- Blobs (512x512, 16 bpp, 107 FPS)
- Perlin noise (512x512, 8 octaves, 16 bpp, 115 FPS)

Also, the normal map and the bump mapping are calculated in real time. I used 16 bit per pixel to have more precision when I get the normal map (for more informations check my High Static Range video). Precision and speed of this engine are awesome. The final result can loop in all horizontal and vertical directions.

CPU: Intel 2 QuadCore 2333 Mhz; RAM: 4 GB DDRII 800Mhz

©2009 Gianpaolo Ingegneri

High Static Range

This demo shows a new feature about the texture generation engine implemented in my Unrelated Framework. The normalmap used by bump mapping is calculated on the base of an heightmap generated with two different methods: Low Static Range and High Static Range. The enviroment bump mapping shows the difference in quality between the two ranges.

The first range uses only 8 bits per pixel that is too low to represent a continuous surface like the sphere generated in this example and as result we can see many rings on the surface during the light effect. On the contrary, an high range of 16 bits per pixel is perfect to have a light effect on a continuous surface infact we don't have any kind of imperfection. I could use the famous High Dynamic Range to generate the height map, but in my opinion it could be too expensive for the use of memory and the lack of speed (32 bits floating point per pixel, or 16 bits half-float has continuous conversions because cpu doesn't support it).

©2009 Gianpaolo Ingegneri

Picture Tube

This is a demo about drawing loop textures with a picture tube technique. The blit functions of my engine can write an alpha source image to a destination buffer preserving the alpha channel information. This technique is useful to design alpha textures and to make some background effect as shown in the picture.

©2008 Gianpaolo Ingegneri

Blit Tech (via software engine)

Finally I've released what I hope will be the first in a long series of demonstrations about the potentiality of my Unrelated Framework. This demo shows some graphic effects to demonstrate the enormous flexibility of the blit engine. Strictly coded via software, it can run on lowend configurations with an excellent frame rate.

There is a custom font format very useful for future development on platforms where there is no freetype support or to resolve the annoying problem that you cannot use the true type hinting informations without a specific license. Moreover, my engine includes other effects like alpha blending, complex bitmap fonts and bump mapping. There is no use of graphics card because all the drawing algorithms have been reprogrammed from scratch by myself and the image buffer is displayed in fullscreen using the basic gdi functions of the operating system. However, in the architecture of my framework you can overload all the via software drawing functions with the graphic card functions of the other famous api like opengl or direct3d.

©2008 Gianpaolo Ingegneri