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How does SDL render?
In SDL2, software rendering is done via structure called SDL_Surface which is then, used to get all color values of all the positions of an image. This surface is then, blitted on to the surface of the SDL_Window to get the image on to the screen. There is no need to have the SDL_Renderer instance!
What does SDL render present do?
SDL_UpdateWindowSurface is equivalent to the SDL 1.2 API SDL_Flip(). On the other side when you use the GPU to render textures and you store your texture on the GPU(this is called hardware accelerated rendering), which you should, you use SDL_RenderPresent . This function tells the GPU to render to the screen.
What is SDL texture?
Textures in SDL have their own data type intuitively called an SDL_Texture. When we deal with SDL textures you need an SDL_Renderer to render it to the screen which is why we declare a global renderer named “gRenderer”.
What is SDL_RenderCopy?
Drawing/Rendering our first image! SDL_RenderCopy() is that method which simply copies the texture to the rectangle coordinates in order to be displayed on to the screen. Take that image below and try rendering it with the same codes as below!
What is an SDL surface?
An SDL surface is just an image data type that contains the pixels of an image along with all data needed to render it. SDL surfaces use software rendering which means it uses the CPU to render. In future tutorials we’ll cover how to render GPU accelerated images.
Does SDL2 use GPU?
Do you want to know a way to get your SDL2 applications running faster? Sweet! The release of SDL2 added the ability to use the GPU. All this time, we’ve been doing software rendering which is where the CPU is doing all the graphics calculations.
Is SDL GPU accelerated?
SDL2 have SDL_Renderer and textures (which are GPU-side images or render targets) and any basic drawing that uses renderer may be accelerated by one or another backend.
How to create a renderer using SDL2?
To create one, we use the SDL_CreateRenderer () function and it takes the following arguments: And 0 or more SDL_RendererFlags OR’d together. I get the first and third, but I don’t know the indices of my rendering drivers. If you don’t want to set it manually, just supply -1 and let SDL2 do the work for you.
How does the texture work in SDL rendercopy?
The texture is blended with the destination based on its blend mode set with SDL_SetTextureBlendMode (). The texture color is affected based on its color modulation set by SDL_SetTextureColorMod ().
How to change the color of the window in SDL?
We can do this by using SDL_RenderClear () and it takes one argument which is a pointer to an SDL_Renderer. If we want to change the color that SDL_RenderClear () uses to clear the window with, we can call SDL_SetRenderDrawColor () which takes a pointer to an SDL_Renderer and red, green, blue and alpha values for each argument.
Is the SDL renderer useless if I use OpenGL?
Note that none of the two involve creating an SDL renderer. In fact, using it would be inappropriate since the two APIs are meant to be mutually exclusive: you should either use one or the other. This answer makes a quick explanation for why you should not mix them.