How do I render multiple textures in OpenGL?

How do I render multiple textures in OpenGL?

Update (some clarification)

1. select the shader program to use ( glUseProgram )
2. for each texture activate in turn the texture unit ( glActiveTexture(GL_TEXTURE_0+i ) and bind the texture (‘glBindTexture`)
3. set the sampler uniforms to the texture units to use ( glUniform1i(…, i) ).

How do you use Bindless textures?

Bindless Textures are a method for having Shaders use a Texture by an integer number rather than by binding them to the OpenGL Context….Direct handle usage

1. Shader stage inputs and outputs (except Fragment Shader outputs).
2. Default block uniform variables (uniforms not in a uniform block).
3. Interface Blocks of all kinds.

How do I load textures into OpenGL rasterizer?

Texture units are like “texture cartridges” of the OpenGL rasterizer. The rasterizer has a limited amount of “cartrige” slots (called texture units ). To load a texture into a texture unit you first select the unit with glActiveTexture, then you load the texture “cardridge” (the texture object) using glBindTexture.

How do you load multiple textures into an array texture?

As the corresponding documentation you link to says: An Array Texture is a Texture where each mipmap level contains an array of images of the same size. So the individual layers of an array texture have to be the same size. Simplifyingly said, an array texture is really just a 3D texture without filtering along the z-axis.

How can I have multiple textures in the same shader?

Different samplers within a shader may “tap” into the same texture unit. By setting the sampler uniform to a texture unit you select which unit you want to sample from. And then you can also have the same texture “slotted” into multiple texture units at the same time.

How are textures stored in a single object?

It’s basically a bunch of 2D textures stacked on top of each other, and stored in a single texture object. The downside is that all textures need to have the same size. If they don’t, you have to use the largest size for the size of the texture array, and you waste memory for the smaller textures.