History of computation and rendering (a guide on what is what)

so have you heard about gtk and wayland and then openGL and just getting confused about their role and what problem each of these softwares are solving ? but more profound qouestion is about rendering, how is it done? is this flow is for only os-based computation and not bare metal ? so in this article we gonna have a deep dive in this and see what is what.

so first lets see how modern embeded systems are displaying and what is going on, and then we gonna go to more complex peices of software which is implemented on operating systems and also will take a look at its history and timline too.

so first I am gonna go with cortext series M ARM embeded systems which basically are microcontrollers and can run only a very small binary made by compiling a c code and not a full fleged Operating system. so basically 3 thins matter in any approach heavilly, first you core processor, then your protocl, last your display device.

STM32 + LCD 1602 Display and I2C 16x2

so in this paradigme fistly there is very basic discplay which is small LCD cells so they have though of data pinns and by connecting 7 pins on data

and the framework is a very small c SDK that can manage these small LCD cells and you can show alphabets and numbers and even like emojis

STM32 + STM32 + OLED

STM32 + LCD Display (FMC) or lcd TFT

so now we can create different stuff both the code base and the method matte, we can not get into messy appraoches, becuase these are actaully foundation and infrastructrue for others to use in their program and create user interfaces

STM32 + ToughGFX or QT

X86 corei7 + VGA/HDMI/Display port/ board + any convential monitor

so now rendering here is not done only by cpu here, we have gpu and there is infrastructure to talk to gpu called opengl or vulkan, now all these are translated to gpu instruction by these the flow is this suppoe GNOME which is built by gtk c++ toolkit generate instructions for wayland and that gives it to opengl and that is send to gpu for rendering or lxqt is built by Qt generate isntruction for x11 then it send to opengl and it send it to cpu/gpu for rendering

Sources

• https://controllerstech.com/interface-lcd-16x2-with-stm32-without-i2c/
• https://diyusthad.com/2019/06/two-ways-of-interfacing-lcd-module-with.html

• https://www.lcd-module.com/support/difference-advantage-betterer-know-how-lcd-tft-oled-ips.html

• https://ieeexplore.ieee.org/document/7926405
• https://www.redalyc.org/journal/6617/661773214004/html/#:~:text=The%20most%20well%2Dknown%20issue%20associated%20with%20revealing,intercepting%20visual%20information%20displayed%20on%20computer%20monitors.&text=Computer%20monitors%20leak%20electromagnetic%20information%20as%20a,the%20display%20principle%20(Mao%20et%20al%2C%202017).