is it possible to draw an image as background and render over it?

[Charrua]

as the topic say.

 

render, clears any 2d graphics already drawn.

 

in blitz, this is done with:

CameraClsMode Camera, 0, 1

 

is there any way/technique in LE of doing this?

 

thank's

 

Juan

[Ma-Shell]

Sadly, there doesn't seem to be any official way for doing so.

This has been discussed in

http://www.leadwerks.com/werkspace/topic/9676-camera-layers/

and

http://www.leadwerks.com/werkspace/topic/9464-rendering-backgroundsforegrounds/

where the latter one shows a work-around, but I would definitely be interested in an official statement from Josh to this, since in my opinion it was a great strength of LE2.5 that you could say something like:

world1->Render();
world2->Render();
context->RenderLighting();

And having the lighting calculated in screenspace only ONCE (not for both render-calls), since this is the way a deferred renderer works (http://www.leadwerks.com/files/Deferred_Rendering_in_Leadwerks_Engine.pdf)

[Charrua]

thank's for your fast response.

 

i'll read carefully the other threads and see what happens, but being watched them on the fly i guess that there is no solution, atm.

 

i need this feature, guess it will be implemented soon.

[Ma-Shell]

I hope so, too.

The workaround presented in my second link has some serious drawbacks, as the lighting is calculated multiple times and some antialiasing-artifacts can be seen, but it works (kind of).

[Charrua]

well, i get what i was looking for!

 

i made simple changes on the code posted by Shadmar (thxs!

 

http://www.leadwerks.com/werkspace/topic/9464-rendering-backgroundsforegrounds/#entry72636

 

i need just a photograph behind and the capability of render 3d objects over it.

 

here is the code:

#include "App.h"
using namespace Leadwerks;
App::App() : window(NULL), context(NULL), world(NULL), camera(NULL) {}
App::~App() { delete world; delete window; }
Vec3 camerarotation;
#if defined (PLATFORM_WINDOWS) || defined (PLATFORM_MACOS)
bool freelookmode = true;
#else
bool freelookmode = false;
#endif

World* backworld = NULL;
Buffer* foreground = NULL;
Buffer* background = NULL;
Texture* backtex = NULL;
Texture* fortex = NULL;
Texture* backImg = NULL;
bool App::Start()
{
//Initialize Steamworks (optional)
/*if (!Steamworks::Initialize())
{
System::Print("Error: Failed to initialize Steam.");
return false;
}*/
//Create a window
window = Leadwerks::Window::Create("cpp_worlds");
//Create a context
context = Context::Create(window);
//Create a world
world = World::Create();
backworld = World::Create();
//create buffer for background
background = Buffer::Create(context->GetWidth(), context->GetHeight(), 1, 0, 0);
backtex = Texture::Create(context->GetWidth(), context->GetHeight(), Texture::RGBA, 0, 1, 0);
//create buffer for foreground
foreground = Buffer::Create(context->GetWidth(), context->GetHeight(), 1, 1, 0);
fortex = Texture::Create(context->GetWidth(), context->GetHeight(), Texture::RGBA, 0, 1, 0);
//create camera for the foreground
World::SetCurrent(world);
camera = Camera::Create();
camera->Move(0, 2, -5);
//Hide the mouse cursor
window->HideMouse();
//Load the map
std::string mapname = System::GetProperty("map", "Maps/start.map");
Map::Load(mapname);
//Move the mouse to the center of the screen
window->SetMousePosition(context->GetWidth() / 2, context->GetHeight() / 2);

//load the background image
backImg = Texture::Load("Materials/backgrounds/backImg.tex");
return true;
}
bool App::Loop()
{
//Close the window to end the program
if (window->Closed()) return false;
//Press escape to end freelook mode
if (window->KeyHit(Key::Escape))
{
 if (!freelookmode) return false;
 freelookmode = false;
 window->ShowMouse();
}
if (freelookmode)
{
 //Keyboard movement
 float strafe = (window->KeyDown(Key:) - window->KeyDown(Key::A))*Leadwerks::Time::GetSpeed() * 0.05;
 float move = (window->KeyDown(Key::W) - window->KeyDown(Key::S))*Leadwerks::Time::GetSpeed() * 0.05;
 camera->Move(strafe, 0, move);
 //Get the mouse movement
 float sx = context->GetWidth() / 2;
 float sy = context->GetHeight() / 2;
 Vec3 mouseposition = window->GetMousePosition();
 float dx = mouseposition.x - sx;
 float dy = mouseposition.y - sy;
 //Adjust and set the camera rotation
 camerarotation.x += dy / 10.0;
 camerarotation.y += dx / 10.0;
 camera->SetRotation(camerarotation);
 //Move the mouse to the center of the screen
 window->SetMousePosition(sx, sy);
}
Leadwerks::Time::Update();
background->Enable();
// draw the background image
context->DrawImage(backImg, 0, 0);
background->Disable();
//Render foreground
foreground->Enable();
world->Update();
world->Render();
foreground->Disable();
//Draw both worlds.
context->Enable();
context->SetBlendMode(Blend::Alpha);
context->DrawImage(background->GetColorTexture(), 0, 0);
context->DrawImage(foreground->GetColorTexture(), 0, 0);
context->SetBlendMode(Blend::Solid);
context->Sync(false);
return true;
}

 

and the result:

 

ok, nothing but a box on it, but this feature is what i was looking for

 

thank's again

 

Juan

[gamecreator]

Thank you for sharing the code!

[Rick]

Yeah, was just thinking what you are asking for is kinda just like a skybox

[Charrua]

i realize that 2 worlds aren't needed.

 

i already have an image for background, so i don't need a background world to render.

 

i simplify the code above (with no mouse look) and with only one world

 

basically what is needed is a buffer to render 3d objects and a background image, the magic is done combining the 2 images with

 

//Draw image, then foreground
context->Enable();
context->SetBlendMode(Blend::Alpha);
context->DrawImage(backImg, 0, 0);
context->DrawImage(foreground->GetColorTexture(), 0, 0);
context->SetBlendMode(Blend::Solid);

 

here the code:

#include "App.h"
using namespace Leadwerks;
App::App() : window(NULL), context(NULL), world(NULL), camera(NULL) {}
App::~App() { delete world; delete window; }

Buffer* foreground = NULL;
Texture* backImg = NULL;
bool App::Start()
{
//Create a window
window = Leadwerks::Window::Create("cpp_worlds");
//Create a context
context = Context::Create(window);
//Create a world
world = World::Create();
//create buffer for foreground
foreground = Buffer::Create(context->GetWidth(), context->GetHeight(), 1, 1, 0);
//create camera for the foreground
World::SetCurrent(world);
camera = Camera::Create();
camera->Move(0, 2, -5);
//Hide the mouse cursor
//window->HideMouse();
//Load the map
std::string mapname = System::GetProperty("map", "Maps/start.map");
Map::Load(mapname);
//Move the mouse to the center of the screen
window->SetMousePosition(context->GetWidth() / 2, context->GetHeight() / 2);

//load the background image
backImg = Texture::Load("Materials/backgrounds/backImg.tex");
return true;
}
bool App::Loop()
{
//Close the window to end the program
if (window->Closed()) return false;

//Render foreground
foreground->Enable();
world->Update();
world->Render();
foreground->Disable();
//Draw image, then foreground
context->Enable();
context->SetBlendMode(Blend::Alpha);
context->DrawImage(backImg, 0, 0);
context->DrawImage(foreground->GetColorTexture(), 0, 0);
context->SetBlendMode(Blend::Solid);
context->Sync(false);
return true;
}

 

btw, where is the buffer documentation?

 

i understand what is happening but i wish to read/know wich other functions/methods are available for buffers

[shadmar]

You can look in classes/buffer.h

[Charrua]

ha!, that's the hard way, i was looking for an easier one

 

but's better than nothing! thxs