4.4) Image viewer and Map viewer

A project log for A2Z Computer

A computer invented, designed and built from scratch. Custom CPU on FPGA.

f4hdkf4hdk 11/18/2016 at 19:240 Comments

The 2 applications manipulate images.

F12 : Exit for both applications.

Image viewer:

This is a very simple application. It displays image on the screen with its filename. You can browse all the images inside the folder where the first image was opened, with the left and right arrows.

Transitions between images are made with the double buffering.

Map Viewer:

It is a little bit more complex. We display a 7MB “raster map file” (bitmap format). This map is stored with 256 x 256 pixels tiles.

For each update of the display, the software determines which tiles have to be displayed for the current X-Y position. Then it draws the tiles already stored in RAM to the hidden frame buffer; then it switches the frame buffer; finally it loads the tiles that are missing from Flash to the RAM and displays them to the displayed frame buffer.