Game Development Reference
In-Depth Information
swaps that need to occur, which can often be a major bottleneck for texture heavy
games.
Finishing the batch
Now that we have begun rendering, we can draw each texture individually. To do
this, we'll add a
Draw
method to our
Texture
class that will handle the rendering
for you. Inside the
Texture
class header, declare the following method prototype
under the
internal
modifier:
void Draw(std::shared_ptr<DirectX::SpriteBatch>
batch);
Once you've done that, implement the method in the
.cpp
file by adding the follow-
ing code:
void
Texture::Draw(std::shared_ptr<DirectX::SpriteBatch>
batch)
{
auto vPos = DirectX::XMLoadFloat2(&_pos);
batch->Draw(_srv.Get(), vPos, nullptr);
}
The main part of this method is the call to
batch->Draw()
, which tells the
SpriteBatch
to draw the texture, or save it for later (depending on which sort mode
you chose).
We need to tell the
Draw
call where to place the sprite on the screen. This is done
through the second parameter, which asks for an
FXMVECTOR
from the
Direc-
tXMath
library that comes with Direct3D and Windows 8. To do this we will have
to load our _
pos
variable, which is stored as
XMFLOAT2 (X, Y)
, into
XMVECTOR
,
which can be passed to the
Draw
function.
After that, we will pass a
nullptr
value to the final parameter, which asks us to
define which region of the texture should be drawn. Here we can define a sub-re-
