public static async Task InitWebGL()
{
await GL.ViewportAsync(0, 0, 1280, 720);
ortho = await M4.Computations.Orthographic(0f, 1280f, 720f, 0f, 1f, 0f);
await GL.ClearColorAsync(0f, 0f, 0.0f, 1.0f);
WebGLShader vertexShader = await CreateShader(ShaderType.VERTEX_SHADER, Shaders.mainVertexShader);
WebGLShader fragmentShader = await CreateShader(ShaderType.FRAGMENT_SHADER, Shaders.mainFragmentShader);
program = await createProgram(vertexShader, fragmentShader);
positionLocation = await GL.GetAttribLocationAsync(program, "positionLocation");
texcoordLocation = await GL.GetAttribLocationAsync(program, "texcoordLocation");
matrixLocation = await GL.GetUniformLocationAsync(program, "matrixLocation");
textureMatrixLocation = await GL.GetUniformLocationAsync(program, "textureMatrixLocation");
textureLocation = await GL.GetUniformLocationAsync(program, "textureLocation");
texPositionBuffer = await GL.CreateBufferAsync();
await GL.BindBufferAsync(BufferType.ARRAY_BUFFER, texPositionBuffer);
float[] positions = { 0f, 0f, 0f, 1f, 1f, 0f, 1f, 0f, 0f, 1f, 1f, 1f };
await GL.BufferDataAsync(BufferType.ARRAY_BUFFER, positions, BufferUsageHint.STATIC_DRAW);
texcoordBuffer = await GL.CreateBufferAsync();
await GL.BindBufferAsync(BufferType.ARRAY_BUFFER, texcoordBuffer);
float[] texcoords = { 0f, 0f, 0f, 1f, 1f, 0f, 1f, 0f, 0f, 1f, 1f, 1f };
await GL.BufferDataAsync(BufferType.ARRAY_BUFFER, texcoords, BufferUsageHint.STATIC_DRAW);
await GL.DisableAsync(EnableCap.DEPTH_TEST);
await GL.EnableAsync(EnableCap.BLEND);
//await GL.EnableAsync(EnableCap.DITHER);
await GL.BlendEquationAsync(BlendingEquation.FUNC_ADD);
//Do not assume the values are premultiplied ( if alpha = 0 then rgb should = 0)
await GL.BlendFuncSeparateAsync(BlendingMode.SRC_ALPHA, BlendingMode.ONE_MINUS_SRC_ALPHA, BlendingMode.ONE, BlendingMode.ONE_MINUS_SRC_ALPHA);
await GL.UseProgramAsync(program);
//Vertex
await GL.BindBufferAsync(BufferType.ARRAY_BUFFER, texPositionBuffer);
await GL.EnableVertexAttribArrayAsync((uint)positionLocation);
await GL.VertexAttribPointerAsync((uint)positionLocation, 2, DataType.FLOAT, false, 0, 0);
//Fragment
await GL.BindBufferAsync(BufferType.ARRAY_BUFFER, texcoordBuffer);
await GL.EnableVertexAttribArrayAsync((uint)texcoordLocation);
await GL.VertexAttribPointerAsync((uint)texcoordLocation, 2, DataType.FLOAT, false, 0, 0);
}
