Offscreen Rendering

[klepto2]

You requested a feature for my IBl Generator, while i have managed to get it to work as a cli, i still need a Hidden window to get all the work done. 

As far as I know vulkan is allowing headless rendering for this, where you don't need an actual surface.

https://github.com/SaschaWillems/Vulkan/blob/master/examples/renderheadless/renderheadless.cpp

It would be nice to have the ability to create a Framebuffer without having a window.

[Josh]

You can render to a texture buffer:

https://www.ultraengine.com/learn/Camera_SetRenderTarget

[klepto2]

I know that i can render to a texture, but i want to run the Vulkan Pipeline without using a window like this:

#include "UltraEngine.h"

using namespace UltraEngine;

void RenderHook(const UltraEngine::Render::VkRenderer& renderer, shared_ptr<Object> extra)
{
    Print("RENDER_HOOK called...");
}

void TransferHook(const UltraEngine::Render::VkRenderer& renderer, shared_ptr<Object> extra)
{
    Print("TRANSFER_HOOK called...");
}

int main(int argc, const char* argv[])
{
    auto cl = ParseCommandLine(argc, argv);

    EngineSettings settings{};
    settings.asyncrender = false;

    //Create a world
    auto world = CreateWorld();

    //Create a framebuffer
    auto framebuffer = CreateTextureBuffer(512,512);
    auto camera = CreateCamera(world);

    world->AddHook(HOOKID_TRANSFER, TransferHook, world, true);
    world->AddHook(HOOKID_RENDER, RenderHook, world, true);

    //Main loop
    for (int frame = 0; frame < 100; frame++)
    {
        world->Update();
        world->Render(framebuffer);
        //camera->Render();
    }
    return 0;
}

but this leads to an assert error at world->Render(), one solution is to create a hidden window, but it would be nicer if it would work even without the need of a window and a correct framebuffer.

[Josh]

Yeah, currently the first call to CreateFramebuffer() triggers the Vulkan initialization, but since Vulkan is headless it would probably be possible to change this without much trouble...