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  1. Total Recall and the 2 Weeks Mystery | It's a Pixel THING - Ep. 118

    The home computer video game based on Total Recall suffered quite a harsh development process and, recently, the rolling demo of the original scrapped ZX Spectrum version was retrieved and made playable for us to try.
    Enjoy!

    Total Recall and the 2 Weeks Mystery | It's a Pixel THING - Ep. 118
  2. Coordinate Rotation using Fixed Point

    The goal here is to quickly rotate points by a certain number of degrees using precalculated SINE/COSINE values and without floating point, e.g. only integers. In order to do that I am using fixed point [1] and a lookup table. So first I want to discuss fixed point a bit to get our feet wet.

    Fixed point is a technique where one designates a number of high bits in an integer to the whole portion and leaves the remaining lower bits to represent a fractional part. This is usually expressed ...
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    3D
  3. My ZX Spectrum Stories | It's a Pixel THING - #special

    This is a compilation of different videos that sums up my personal experience, and southwestern Europe point of view, with the good old ZX Spectrum that is already 35 years old.

    My ZX Spectrum Stories | It's a Pixel THING - #special
  4. HUGE Donation | It's a Pixel THING - #special

    Check this HUGE donation that was sent to the channel!

    HUGE Donation | It's a Pixel THING - #special
  5. DDA Texture Mapping [Part 2]

    Since the first part I blogged a few weeks ago, I've written the method QTEX() [1] which maps an 8x8x1 (monochrome) texture onto a quadrilateral (four vertices). This uses fixed point for all coordinates and deltas so there are rounding errors, especially in the inner loop when drawing a scan line because I use a single byte per U/V delta. In fact, here's an image which demonstrates the problem:

    Click image for larger version. 

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    No matter how I adjust the U/V coordinates ...
    Tags: cga, x86 Add / Edit Tags
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    Asm
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