private CubemapDataProvider GetCubemapDataProvider(Bitmap totalBmp)
{
int width = totalBmp.Width / 4, height = totalBmp.Height / 3;
var top = new Bitmap(width, height);
using (var g = Graphics.FromImage(top))
{
g.DrawImage(totalBmp, new Rectangle(0, 0, width, height), new Rectangle(width, 0, width, height), GraphicsUnit.Pixel);
}
top.RotateFlip(RotateFlipType.Rotate180FlipNone); // apparently it doesnt like aligning the top so we have to do this bullshit
var left = new Bitmap(width, height);
using (var g = Graphics.FromImage(left))
{
g.DrawImage(totalBmp, new Rectangle(0, 0, width, height), new Rectangle(0, height, width, height), GraphicsUnit.Pixel);
}
var front = new Bitmap(width, height);
using (var g = Graphics.FromImage(front))
{
g.DrawImage(totalBmp, new Rectangle(0, 0, width, height), new Rectangle(width, height, width, height), GraphicsUnit.Pixel);
}
var right = new Bitmap(width, height);
using (var g = Graphics.FromImage(right))
{
g.DrawImage(totalBmp, new Rectangle(0, 0, width, height), new Rectangle(width * 2, height, width, height), GraphicsUnit.Pixel);
}
var back = new Bitmap(width, height);
using (var g = Graphics.FromImage(back))
{
g.DrawImage(totalBmp, new Rectangle(0, 0, width, height), new Rectangle(width * 3, height, width, height), GraphicsUnit.Pixel);
}
var bottom = new Bitmap(width, height);
using (var g = Graphics.FromImage(bottom))
{
g.DrawImage(totalBmp, new Rectangle(0, 0, width, height), new Rectangle(width, height * 2, width, height), GraphicsUnit.Pixel);
}
var flip = RotateFlipType.Rotate180FlipY;
right.RotateFlip(flip); left.RotateFlip(flip);
top.RotateFlip(flip); bottom.RotateFlip(RotateFlipType.Rotate180FlipX);
back.RotateFlip(flip); front.RotateFlip(flip);
#if SKYBOX_SAVE
right.Save("right.png"); left.Save("left.png");
top.Save("top.png"); bottom.Save("bottom.png");
back.Save("back.png"); front.Save("front.png");
#endif
var result = new CubemapDataProvider(right, left, top, bottom, back, front);
return(result);
}
// pbr: create an irradiance cubemap.
private Texture LoadIrradianceMap()
{
var dataProvider = new CubemapDataProvider(null, null, null, null, null, null);
var storage = new CubemapTexImage2D(GL.GL_RGB16F, 32, 32, GL.GL_RGB, GL.GL_FLOAT, dataProvider);
var envCubeMap = new Texture(storage,
new TexParameteri(TexParameter.PropertyName.TextureWrapS, (int)GL.GL_CLAMP_TO_EDGE),
new TexParameteri(TexParameter.PropertyName.TextureWrapT, (int)GL.GL_CLAMP_TO_EDGE),
new TexParameteri(TexParameter.PropertyName.TextureWrapR, (int)GL.GL_CLAMP_TO_EDGE),
new TexParameteri(TexParameter.PropertyName.TextureMinFilter, (int)GL.GL_LINEAR),
new TexParameteri(TexParameter.PropertyName.TextureMagFilter, (int)GL.GL_LINEAR));
envCubeMap.Initialize();
return(envCubeMap);
}
private Texture LoadPrefliterMap()
{
var dataProvider = new CubemapDataProvider(null, null, null, null, null, null);
var storage = new CubemapTexImage2D(GL.GL_RGB16F, 128, 128, GL.GL_RGB, GL.GL_FLOAT, dataProvider, 6);
var prefliterMap = new Texture(storage, new MipmapBuilder(),
new TexParameteri(TexParameter.PropertyName.TextureWrapS, (int)GL.GL_CLAMP_TO_EDGE),
new TexParameteri(TexParameter.PropertyName.TextureWrapT, (int)GL.GL_CLAMP_TO_EDGE),
new TexParameteri(TexParameter.PropertyName.TextureWrapR, (int)GL.GL_CLAMP_TO_EDGE),
new TexParameteri(TexParameter.PropertyName.TextureMinFilter, (int)GL.GL_LINEAR_MIPMAP_LINEAR),
new TexParameteri(TexParameter.PropertyName.TextureMagFilter, (int)GL.GL_LINEAR));
prefliterMap.Initialize();
return(prefliterMap);
}
// pbr: setup cubemap to render to and attach to framebuffer
private Texture LoadEnvCubeMap()
{
var dataProvider = new CubemapDataProvider(null, null, null, null, null, null);
var storage = new CubemapTexImage2D(GL.GL_RGB16F, 512, 512, GL.GL_RGB, GL.GL_FLOAT, dataProvider);
var envCubeMap = new Texture(storage,
new MipmapBuilder(), // This is can also be done inside CubemapNode.DoInitialize().
new TexParameteri(TexParameter.PropertyName.TextureWrapS, (int)GL.GL_CLAMP_TO_EDGE),
new TexParameteri(TexParameter.PropertyName.TextureWrapT, (int)GL.GL_CLAMP_TO_EDGE),
new TexParameteri(TexParameter.PropertyName.TextureWrapR, (int)GL.GL_CLAMP_TO_EDGE),
new TexParameteri(TexParameter.PropertyName.TextureMinFilter, (int)GL.GL_LINEAR_MIPMAP_LINEAR),
new TexParameteri(TexParameter.PropertyName.TextureMagFilter, (int)GL.GL_LINEAR));
envCubeMap.Initialize();
return(envCubeMap);
}
private Texture GetCubemapTexture(Bitmap[] bitmaps)
{
var dataProvider = new CubemapDataProvider(
bitmaps[0], bitmaps[1], bitmaps[2], bitmaps[3], bitmaps[4], bitmaps[5]);
var storage = new CubemapTexImage2D((int)GL.GL_RGBA, bitmaps[0].Width, bitmaps[0].Height, 0, GL.GL_BGRA, GL.GL_UNSIGNED_BYTE, dataProvider);
var texture = new Texture(TextureTarget.TextureCubeMap, storage,
new TexParameteri(TexParameter.PropertyName.TextureMagFilter, (int)GL.GL_LINEAR),
new TexParameteri(TexParameter.PropertyName.TextureMinFilter, (int)GL.GL_LINEAR),
new TexParameteri(TexParameter.PropertyName.TextureWrapS, (int)GL.GL_CLAMP_TO_EDGE),
new TexParameteri(TexParameter.PropertyName.TextureWrapT, (int)GL.GL_CLAMP_TO_EDGE),
new TexParameteri(TexParameter.PropertyName.TextureWrapR, (int)GL.GL_CLAMP_TO_EDGE));
texture.Initialize();
return(texture);
}
// pbr: create a pre-filter cubemap.
private Texture LoadPrefilterMap()
{
var dataProvider = new CubemapDataProvider(null, null, null, null, null, null);
var storage = new CubemapTexImage2D(GL.GL_RGB16F, 128, 128, GL.GL_RGB, GL.GL_FLOAT, dataProvider);
var envCubeMap = new Texture(storage,
// generate mipmaps for the cubemap so OpenGL automatically allocates the required memory.
new MipmapBuilder(),
new TexParameteri(TexParameter.PropertyName.TextureWrapS, (int)GL.GL_CLAMP_TO_EDGE),
new TexParameteri(TexParameter.PropertyName.TextureWrapT, (int)GL.GL_CLAMP_TO_EDGE),
new TexParameteri(TexParameter.PropertyName.TextureWrapR, (int)GL.GL_CLAMP_TO_EDGE),
// be sure to set minifcation filter to mip_linear
new TexParameteri(TexParameter.PropertyName.TextureMinFilter, (int)GL.GL_LINEAR_MIPMAP_LINEAR),
new TexParameteri(TexParameter.PropertyName.TextureMagFilter, (int)GL.GL_LINEAR));
envCubeMap.Initialize();
return(envCubeMap);
}
