public static DemoSource LoadSource(string filePathName)
{
var source = new DemoSource();
// Check the file name suffix to determine what type of shader this is
if(Path.GetExtension(filePathName) == ".fsh")
{
source.ShaderType = All.FragmentShader;
}
else if(Path.GetExtension(filePathName) == ".vsh")
{
source.ShaderType = All.VertexShader;
}
else
{
// Unknown
source.ShaderType = (All)0;
}
var fileContent = File.ReadAllText(filePathName);
source.String = fileContent;
return source;
}
int BuildProgramWithVertexSource(DemoSource vertexSource, DemoSource fragmentSource, bool hasNormal, bool hasTexcoord)
{
int prgName = 0;
int logLength = 0, status = 0;
// String to pass to Gl.ShaderSource
var sourceString = string.Empty;
// Determine if GLSL version 140 is supported by this context.
// We'll use this info to generate a GLSL shader source string
// with the proper version preprocessor string prepended
float glLanguageVersion;
var glVerString = GL.GetString( StringName.ShadingLanguageVersion);
glLanguageVersion = Convert.ToSingle(glVerString.Replace("OpenGL ES GLSL ES", string.Empty));
// All.ShadingLanguageVersion returns the version standard version form
// with decimals, but the GLSL version preprocessor directive simply
// uses integers (thus 1.10 should 110 and 1.40 should be 140, etc.)
// We multiply the floating point number by 100 to get a proper
// number for the GLSL preprocessor directive
int version = Convert.ToInt32(100 * glLanguageVersion);
prgName = GL.CreateProgram();
// Indicate the attribute indicies on which vertex arrays will be
// set with GL.VertexAttribPointer
// See BuildVAO to see where vertex array are actually set
GL.BindAttribLocation(prgName, POS_ATTRIB_IDX, "inPosition");
if(hasNormal)
{
GL.BindAttribLocation(prgName, NORMAL_ATTRIB_IDX, "inNormal");
}
if(hasTexcoord)
{
GL.BindAttribLocation(prgName, TEXCOORD_ATTRIB_IDX, "inTexcoord");
}
//////////////////////////////////////
// Specify and compile VertexShader //
//////////////////////////////////////
// Prepend our vertex shader source string with the supported GLSL version so
// the shader will work on ES, Legacy, and OpenGL 3.2 Core Profile contexts
sourceString = string.Format("#version {0}\n{1}", version, vertexSource.String);
int vertexShader;
if(!CompileShader(out vertexShader, ShaderType.VertexShader, sourceString))
{
Console.WriteLine("Could not Compile Vertex Shader");
return 0;
}
GL.AttachShader(prgName, vertexShader);
/////////////////////////////////////////
// Specify and compile Fragment Shader //
/////////////////////////////////////////
sourceString = string.Format("#version {0}\n{1}", version, fragmentSource.String);
int fragShader;
if(!CompileShader(out fragShader, ShaderType.FragmentShader, sourceString))
{
Console.WriteLine("Could not Compile Fragment Shader");
return 0;
}
// Attach the fragment shader to our program
GL.AttachShader(prgName, fragShader);
//////////////////////
// Link the program //
//////////////////////
GL.LinkProgram(prgName);
GL.GetProgram(prgName, ProgramParameter.InfoLogLength, out logLength);
if(logLength > 0)
{
var log = new StringBuilder(logLength);
GL.GetProgramInfoLog(prgName, logLength, out logLength, log);
Console.WriteLine("Program link log: " + log.ToString());
}
GL.GetProgram(prgName, ProgramParameter.LinkStatus, out status);
if(status == 0)
{
Console.WriteLine("Failed to link program");
return 0;
}
GL.ValidateProgram(prgName);
GL.GetProgram(prgName, ProgramParameter.InfoLogLength, out logLength);
if(logLength > 0)
{
var log = new StringBuilder(logLength);
GL.GetProgramInfoLog(prgName, logLength, out logLength, log);
Console.WriteLine("Program validate log: " + log.ToString());
}
GL.GetProgram(prgName, ProgramParameter.ValidateStatus, out status);
if(status == 0)
{
Console.WriteLine("Failed to validate program");
return 0;
}
GL.UseProgram(prgName);
///////////////////////////////////////
// Setup common program input points //
///////////////////////////////////////
int sampleLoc = GL.GetUniformLocation(prgName, "diffuseTexture");
// Indicate that the diffuse texture will be bound to texture uint 0
var uint0 = 0;
GL.Uniform1 (sampleLoc, uint0);
GetGLError();
return prgName;
}
