RACharts

Telegram's contest chart implementation using OpenGL.

1st stage - 4th place

Telegram rated the app as nice as fast but charts were placed in different screens.

2nd stage - 3rd place & ratings 1st place

The app got 4/5 admins' votes and the 1st place in the constest's rating but I didn't implement the bonus goals.

Implementations remarks

• Theme change supports any property like color, font, text or even views to be changed;
• The app could support any number of themes not just black or white.
• Y scale can separately calculate up to N charts;
• Y scale calculator is replaceable. For now it has 3 implementations: sum, common and separate Y calculations.
• Y renderer is replaceable. For now it renders horizontal lines for 1 or 2 charts;
• X renderer is replaceable. For now it renders dates under the chart;
• Chart renderer is replaceable. For now it has 3 implementations: line, bar and area;

What could be done better

• Y and X renderers implementation using OpenGL;
• Simplier interval selection view;
• Replaceable selection style;
• Line joints;
• 3rd chart has issues with Pears rendering (only on real devices);