protected override void OnLoad()
{
VSync = VSyncMode.Off;
// Check for necessary capabilities:
var extensions = GL.GetString(StringName.Extensions);
if (!GL.GetString(StringName.Extensions).Contains("GL_ARB_shading_language"))
{
throw new NotSupportedException(String.Format("This example requires OpenGL 2.0. Found {0}. Aborting.",
GL.GetString(StringName.Version).Substring(0, 3)));
}
if (!extensions.Contains("GL_ARB_texture_compression") ||
!extensions.Contains("GL_EXT_texture_compression_s3tc"))
{
throw new NotSupportedException("This example requires support for texture compression. Aborting.");
}
var temp = new int[1];
GL.GetInteger(GetPName.MaxTextureImageUnits, out temp[0]);
Trace.WriteLine(temp[0] + " TMU's for Fragment Shaders found. (2 required)");
GL.GetInteger(GetPName.MaxVaryingFloats, out temp[0]);
Trace.WriteLine(temp[0] + " varying floats between VS and FS allowed. (6 required)");
GL.GetInteger(GetPName.MaxVertexUniformComponents, out temp[0]);
Trace.WriteLine(temp[0] + " uniform components allowed in Vertex Shader. (6 required)");
GL.GetInteger(GetPName.MaxFragmentUniformComponents, out temp[0]);
Trace.WriteLine(temp[0] + " uniform components allowed in Fragment Shader. (11 required)");
Trace.WriteLine("");
// load textures
TextureLoaderParameters.MagnificationFilter = TextureMagFilter.Linear;
TextureLoaderParameters.MinificationFilter = TextureMinFilter.LinearMipmapLinear;
TextureLoaderParameters.WrapModeS = TextureWrapMode.ClampToBorder;
TextureLoaderParameters.WrapModeT = TextureWrapMode.ClampToBorder;
TextureLoaderParameters.EnvMode = TextureEnvMode.Modulate;
uint handle;
TextureTarget target;
ImageDDS.LoadFromDisk(TextureDiffuseHeightFilename, out handle, out target);
_textureDiffuseHeight = TextureFactory.AquireTexture2D((int)handle);
Trace.WriteLine("Loaded " + TextureDiffuseHeightFilename + " with handle " + handle + " as " + target);
ImageDDS.LoadFromDisk(TextureNormalGlossFilename, out handle, out target);
_textureNormalGloss = TextureFactory.AquireTexture2D((int)handle);
Trace.WriteLine("Loaded " + TextureNormalGlossFilename + " with handle " + handle + " as " + target);
Trace.WriteLine("End of Texture Loading. GL Error: " + GL.GetError());
Trace.WriteLine("");
// initialize buffer
var normal = Vector3.UnitZ;
var tangent = Vector3.UnitX;
var vertices = new[]
{
new Vertex
{
Position = new Vector3(-1, -1, 0),
TexCoord = new Vector2(0, 0),
Normal = normal,
Tangent = tangent
},
new Vertex
{
Position = new Vector3(1, -1, 0),
TexCoord = new Vector2(1, 0),
Normal = normal,
Tangent = tangent
},
new Vertex
{
Position = new Vector3(-1, 1, 0),
TexCoord = new Vector2(0, 1),
Normal = normal,
Tangent = tangent
},
new Vertex
{
Position = new Vector3(1, 1, 0),
TexCoord = new Vector2(1, 1),
Normal = normal,
Tangent = tangent
}
};
_buffer = new Buffer <Vertex>();
_buffer.Init(BufferTarget.ArrayBuffer, vertices);
// load shader
_program = ProgramFactory.Create <ParallaxProgram>();
_program.Use();
// set up vertex array
_vao = new VertexArray();
_vao.Bind();
// bind vertex attributes
// the buffer layout is defined by the Vertex struct:
// data X Y Z NX NY NZ TX TY TZ U V *next vertex*
// offset 0 4 8 12 16 20 24 28 32 36 40 44
// having to work with offsets could be prevented by using seperate buffer objects for each attribute,
// but that might reduce performance and can get annoying as well.
// performance increase could also be achieved by improving coherent read access
// by padding the struct so that each attribute begins at a multiple of 16 bytes, i.e. 4-floats
// because the GPU can then read all 4 floats at once. I did not do that here to keep it simple.
_vao.BindAttribute(_program.InPosition, _buffer);
_vao.BindAttribute(_program.InNormal, _buffer, 12);
_vao.BindAttribute(_program.InTangent, _buffer, 24);
_vao.BindAttribute(_program.InTexCoord, _buffer, 36);
// set camera position
Camera.DefaultState.Position = new Vector3(0, 0, 3);
Camera.ResetToDefault();
// set state
GL.ClearColor(0.2f, 0f, 0.4f, 0f);
GL.PointSize(10f);
GL.Disable(EnableCap.Dither);
GL.FrontFace(FrontFaceDirection.Ccw);
GL.PolygonMode(MaterialFace.Front, PolygonMode.Fill);
GL.PolygonMode(MaterialFace.Back, PolygonMode.Line);
}
