public static void Start()
{
Bitmap bMap = new Bitmap(@"Textures/bricks.jpg");
using (var w = new GameWindow(720, 480, null, "ComGr", GameWindowFlags.Default, DisplayDevice.Default, 4, 0, OpenTK.Graphics.GraphicsContextFlags.ForwardCompatible))
{
int hProgram = 0;
int hTxtr = 0;
float alpha = 0f;
int vaoTriangle = 0;
int[] triangleIndices = null;
int vboTriangleIndices = 0;
w.Load += (o, ea) =>
{
//set up opengl
GL.Enable(EnableCap.FramebufferSrgb);
GL.ClearColor(0.5f, 0.5f, 0.5f, 0);
GL.ClearDepth(1f);
GL.Enable(EnableCap.DepthTest);
GL.DepthFunc(DepthFunction.Less);
//load, compile and link shaders
//see https://www.khronos.org/opengl/wiki/Vertex_Shader
var VertexShaderSource = @"
#version 400 core
in vec3 pos;
in vec2 textureCoordinates;
in vec3 normals;
uniform mat4 m;
uniform mat4 proj;
out vec2 txtCoords;
out vec3 norms;
out vec3 point;
void main()
{
gl_Position = proj * vec4(pos,1);
txtCoords = textureCoordinates;
vec4 hNorm = vec4(normals, 0);
vec4 hPos = vec4(pos,1);
norms = (m * hNorm).xyz;
point = (m * hPos).xyz;
}
";
var hVertexShader = GL.CreateShader(ShaderType.VertexShader);
GL.ShaderSource(hVertexShader, VertexShaderSource);
GL.CompileShader(hVertexShader);
GL.GetShader(hVertexShader, ShaderParameter.CompileStatus, out int status);
if (status != 1)
{
throw new Exception(GL.GetShaderInfoLog(hVertexShader));
}
//see https://www.khronos.org/opengl/wiki/Fragment_Shader
var FragmentShaderSource = @"
#version 400 core
in vec2 txtCoords;
in vec3 norms;
in vec3 point;
uniform sampler2D bricks;
out vec4 color;
void main()
{
vec4 txtColor = texture(bricks, txtCoords);
vec4 col = vec4(txtColor.b, txtColor.g, txtColor.r, 1);
vec3 lPos = vec3(0, 0, 5);
vec4 lCol = vec4(1);
vec3 eye = vec3(0, 0, 0);
vec3 PL = normalize(lPos - point);
vec3 diff = vec3(0);
float nL = dot(norms, PL);
if(nL >= 0) { diff = lCol.xyz * col.xyz * nL; }
vec3 viewDir = normalize(eye - point);
vec3 reflectDir = reflect(-PL, norms);
float fSpec = pow(max(dot(viewDir, reflectDir), 0.0), 128);
vec3 spec = 0.5 * fSpec * lCol.rgb;
color = vec4(diff, 1) + vec4(spec, 1);
}
";
var hFragmentShader = GL.CreateShader(ShaderType.FragmentShader);
GL.ShaderSource(hFragmentShader, FragmentShaderSource);
GL.CompileShader(hFragmentShader);
GL.GetShader(hFragmentShader, ShaderParameter.CompileStatus, out status);
if (status != 1)
{
throw new Exception(GL.GetShaderInfoLog(hFragmentShader));
}
//link shaders to a program
hProgram = GL.CreateProgram();
GL.AttachShader(hProgram, hFragmentShader);
GL.AttachShader(hProgram, hVertexShader);
GL.LinkProgram(hProgram);
GL.GetProgram(hProgram, GetProgramParameterName.LinkStatus, out status);
if (status != 1)
{
throw new Exception(GL.GetProgramInfoLog(hProgram));
}
//upload model vertices to a vbo
var triangleVertices = OpenGLArrays.TriangleVertices();
var vboTriangleVertices = GL.GenBuffer();
GL.BindBuffer(BufferTarget.ArrayBuffer, vboTriangleVertices);
GL.BufferData(BufferTarget.ArrayBuffer, triangleVertices.Length * sizeof(float), triangleVertices, BufferUsageHint.StaticDraw);
// upload model indices to a vbo
triangleIndices = OpenGLArrays.TriangleIndices();
vboTriangleIndices = GL.GenBuffer();
GL.BindBuffer(BufferTarget.ElementArrayBuffer, vboTriangleIndices);
GL.BufferData(BufferTarget.ElementArrayBuffer, triangleIndices.Length * sizeof(int), triangleIndices, BufferUsageHint.StaticDraw);
// upload texture coords to a vbo
var textureCoords = OpenGLArrays.TextureCoords();
var vboTexCoords = GL.GenBuffer();
GL.BindBuffer(BufferTarget.ArrayBuffer, vboTexCoords);
GL.BufferData(BufferTarget.ArrayBuffer, textureCoords.Length * sizeof(float), textureCoords, BufferUsageHint.StaticDraw);
// upload normals to a vbo
var normals = OpenGLArrays.Normals();
var vboNormals = GL.GenBuffer();
GL.BindBuffer(BufferTarget.ArrayBuffer, vboNormals);
GL.BufferData(BufferTarget.ArrayBuffer, normals.Length * sizeof(float), normals, BufferUsageHint.StaticDraw);
//set up a vao
vaoTriangle = GL.GenVertexArray();
GL.BindVertexArray(vaoTriangle);
var posAttribIndex = GL.GetAttribLocation(hProgram, "pos");
if (posAttribIndex != -1)
{
GL.EnableVertexAttribArray(posAttribIndex);
GL.BindBuffer(BufferTarget.ArrayBuffer, vboTriangleVertices);
GL.VertexAttribPointer(posAttribIndex, 3, VertexAttribPointerType.Float, false, 0, 0);
}
var txtAttribIndex = GL.GetAttribLocation(hProgram, "textureCoordinates");
if (txtAttribIndex != -1)
{
GL.EnableVertexAttribArray(txtAttribIndex);
GL.BindBuffer(BufferTarget.ArrayBuffer, vboTexCoords);
GL.VertexAttribPointer(txtAttribIndex, 2, VertexAttribPointerType.Float, false, 0, 0);
}
var normAttribIndex = GL.GetAttribLocation(hProgram, "normals");
if (normAttribIndex != -1)
{
GL.EnableVertexAttribArray(normAttribIndex);
GL.BindBuffer(BufferTarget.ArrayBuffer, vboNormals);
GL.VertexAttribPointer(normAttribIndex, 3, VertexAttribPointerType.Float, false, 0, 0);
}
// Setup Texture
GL.GenTextures(1, out hTxtr);
GL.BindTexture(TextureTarget.Texture2D, hTxtr);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Nearest);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int)TextureMinFilter.LinearMipmapLinear);
GL.PixelStore(PixelStoreParameter.UnpackAlignment, 1);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, (int)TextureWrapMode.Repeat);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (int)TextureWrapMode.Repeat);
// Copy bitmapdata into a byte array
BitmapData data = bMap.LockBits(new Rectangle(0, 0, bMap.Width, bMap.Height),
ImageLockMode.ReadOnly, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
int bLen = Math.Abs(data.Stride) * data.Height;
byte[] imgData = new byte[bLen];
Marshal.Copy(data.Scan0, imgData, 0, bLen);
bMap.UnlockBits(data);
GL.TexImage2D(TextureTarget.Texture2D, 0, PixelInternalFormat.Srgb8, bMap.Width, bMap.Height, 0, OpenTK.Graphics.OpenGL4.PixelFormat.Rgb, PixelType.UnsignedByte, imgData);
GL.GenerateMipmap(GenerateMipmapTarget.Texture2D);
//check for errors during all previous calls
var error = GL.GetError();
if (error != ErrorCode.NoError)
{
throw new Exception(error.ToString());
}
};
w.UpdateFrame += (o, fea) =>
{
//perform logic
alpha += 0.5f * (float)fea.Time;
};
w.RenderFrame += (o, fea) =>
{
//clear screen and z-buffer
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
//switch to our shader
GL.UseProgram(hProgram);
GL.ActiveTexture(TextureUnit.Texture0);
GL.BindTexture(TextureTarget.Texture2D, hTxtr);
var txtrUniformIndex = GL.GetUniformLocation(hProgram, "bricks");
if (txtrUniformIndex != -1)
{
GL.Uniform1(txtrUniformIndex, 0);
}
var scale = Matrix4.CreateScale(0.5f);
var rotateY = Matrix4.CreateRotationY(alpha);
var rotateX = Matrix4.CreateRotationX(alpha);
var modelView =
//model
Matrix4.Identity
//view
* Matrix4.LookAt(new Vector3(0, 0, -10), new Vector3(0, 0, 0), new Vector3(0, 1, 0)); //view
var projection =
//projection
Matrix4.CreatePerspectiveFieldOfView(45 * (float)(Math.PI / 180d), w.ClientRectangle.Width / (float)w.ClientRectangle.Height, 0.1f, 100f);
var M = rotateX * rotateY * modelView;
var mAttribIndex = GL.GetUniformLocation(hProgram, "m");
if (mAttribIndex != -1)
{
GL.UniformMatrix4(mAttribIndex, false, ref M);
}
var MVP = M * projection;
var projAttribIndex = GL.GetUniformLocation(hProgram, "proj");
if (projAttribIndex != -1)
{
GL.UniformMatrix4(projAttribIndex, false, ref MVP);
}
//render our model
GL.BindVertexArray(vaoTriangle);
GL.BindBuffer(BufferTarget.ElementArrayBuffer, vboTriangleIndices);
GL.DrawElements(PrimitiveType.Triangles, triangleIndices.Length, DrawElementsType.UnsignedInt, 0);
//display
w.SwapBuffers();
var error = GL.GetError();
if (error != ErrorCode.NoError)
{
throw new Exception(error.ToString());
}
};
w.Resize += (o, ea) =>
{
GL.Viewport(w.ClientRectangle);
};
w.Run();
}
}
public static void Start()
{
Bitmap bMap = new Bitmap(@"Textures/bricks.jpg");
using (var w = new GameWindow(720, 480, null, "ComGr", GameWindowFlags.Default, DisplayDevice.Default, 4, 0, OpenTK.Graphics.GraphicsContextFlags.ForwardCompatible))
{
int hProgram = 0;
float alpha = 0f;
int vaoTriangle = 0;
int[] triangleIndices = null;
int vboTriangleIndices = 0;
w.Load += (o, ea) =>
{
//set up opengl
GL.ClearColor(0.5f, 0.5f, 0.5f, 0);
//GL.ClearDepth(1f);
GL.Enable(EnableCap.DepthTest);
GL.DepthMask(true);
GL.DepthRange(0, 50);
//GL.DepthFunc(DepthFunction.Less);
GL.Enable(EnableCap.Blend);
GL.BlendFunc(BlendingFactor.One, BlendingFactor.One);
GL.Disable(EnableCap.CullFace);
//load, compile and link shaders
//see https://www.khronos.org/opengl/wiki/Vertex_Shader
var VertexShaderSource = @"
#version 400 core
in vec3 pos;
in vec3 normals;
uniform mat4 m;
uniform mat4 proj;
out vec3 norms;
out vec3 point;
void main()
{
gl_Position = proj * vec4(pos,1);
vec4 hNorm = vec4(normals, 0);
vec4 hPos = vec4(pos,1);
norms = (m * hNorm).xyz;
point = (m * hPos).xyz;
}
";
var hVertexShader = GL.CreateShader(ShaderType.VertexShader);
GL.ShaderSource(hVertexShader, VertexShaderSource);
GL.CompileShader(hVertexShader);
GL.GetShader(hVertexShader, ShaderParameter.CompileStatus, out int status);
if (status != 1)
{
throw new Exception(GL.GetShaderInfoLog(hVertexShader));
}
//see https://www.khronos.org/opengl/wiki/Fragment_Shader
var FragmentShaderSource = @"
#version 400 core
in vec3 norms;
in vec3 point;
uniform vec4 oClr;
out vec4 color;
void main()
{
//vec4 clr = vec4(1, 0, 0, 0.5);
vec4 tmpClr = oClr;
vec3 lPos = vec3(0, 0, 5);
vec4 lCol = vec4(0.8, 0.8, 0.8, 1);
vec3 eye = vec3(0, 0, 0);
vec3 PL = normalize(lPos - point);
vec3 diff = vec3(0);
float nL = dot(norms, PL);
if (tmpClr.a < 1)
{
nL = max(nL, 1 - nL);
}
if(nL >= 0) { diff = lCol.xyz * tmpClr.xyz * nL; }
vec3 viewDir = normalize(eye - point);
vec3 reflectDir = reflect(-PL, norms);
float fSpec = pow(max(dot(viewDir, reflectDir), 0.0), 128);
vec3 spec = 0.5 * fSpec * lCol.rgb;
color = vec4(diff + spec, oClr.a);
}
";
var hFragmentShader = GL.CreateShader(ShaderType.FragmentShader);
GL.ShaderSource(hFragmentShader, FragmentShaderSource);
GL.CompileShader(hFragmentShader);
GL.GetShader(hFragmentShader, ShaderParameter.CompileStatus, out status);
if (status != 1)
{
throw new Exception(GL.GetShaderInfoLog(hFragmentShader));
}
//link shaders to a program
hProgram = GL.CreateProgram();
GL.AttachShader(hProgram, hFragmentShader);
GL.AttachShader(hProgram, hVertexShader);
GL.LinkProgram(hProgram);
GL.GetProgram(hProgram, GetProgramParameterName.LinkStatus, out status);
if (status != 1)
{
throw new Exception(GL.GetProgramInfoLog(hProgram));
}
//upload model vertices to a vbo
var triangleVertices = OpenGLArrays.TriangleVertices();
var vboTriangleVertices = GL.GenBuffer();
GL.BindBuffer(BufferTarget.ArrayBuffer, vboTriangleVertices);
GL.BufferData(BufferTarget.ArrayBuffer, triangleVertices.Length * sizeof(float), triangleVertices, BufferUsageHint.StaticDraw);
// upload model indices to a vbo
triangleIndices = OpenGLArrays.TriangleIndices();
vboTriangleIndices = GL.GenBuffer();
GL.BindBuffer(BufferTarget.ElementArrayBuffer, vboTriangleIndices);
GL.BufferData(BufferTarget.ElementArrayBuffer, triangleIndices.Length * sizeof(int), triangleIndices, BufferUsageHint.StaticDraw);
// upload normals to a vbo
var normals = OpenGLArrays.Normals();
var vboNormals = GL.GenBuffer();
GL.BindBuffer(BufferTarget.ArrayBuffer, vboNormals);
GL.BufferData(BufferTarget.ArrayBuffer, normals.Length * sizeof(float), normals, BufferUsageHint.StaticDraw);
//set up a vao
vaoTriangle = GL.GenVertexArray();
GL.BindVertexArray(vaoTriangle);
var posAttribIndex = GL.GetAttribLocation(hProgram, "pos");
if (posAttribIndex != -1)
{
GL.EnableVertexAttribArray(posAttribIndex);
GL.BindBuffer(BufferTarget.ArrayBuffer, vboTriangleVertices);
GL.VertexAttribPointer(posAttribIndex, 3, VertexAttribPointerType.Float, false, 0, 0);
}
var normAttribIndex = GL.GetAttribLocation(hProgram, "normals");
if (normAttribIndex != -1)
{
GL.EnableVertexAttribArray(normAttribIndex);
GL.BindBuffer(BufferTarget.ArrayBuffer, vboNormals);
GL.VertexAttribPointer(normAttribIndex, 3, VertexAttribPointerType.Float, false, 0, 0);
}
//check for errors during all previous calls
var error = GL.GetError();
if (error != ErrorCode.NoError)
{
throw new Exception(error.ToString());
}
};
w.UpdateFrame += (o, fea) =>
{
//perform logic
alpha += 0.5f * (float)fea.Time;
};
w.RenderFrame += (o, fea) =>
{
//clear screen and z-buffer
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
//switch to our shader
GL.UseProgram(hProgram);
GL.DepthMask(true);
GL.Disable(EnableCap.Blend);
var scale = Matrix4.CreateScale(0.5f);
var rotateY = Matrix4.CreateRotationY(alpha);
var rotateX = Matrix4.CreateRotationX(alpha);
var modelView =
//model
Matrix4.Identity
//view
* Matrix4.LookAt(new Vector3(0, 0, -10), new Vector3(0, 0, 0), new Vector3(0, 1, 0)); //view
var projection =
//projection
Matrix4.CreatePerspectiveFieldOfView(45 * (float)(Math.PI / 180d), w.ClientRectangle.Width / (float)w.ClientRectangle.Height, 0.1f, 100f);
// Solid Cube
var translate = Matrix4.CreateTranslation(-1.3f, 0, 0);
var M = rotateX * rotateY * translate * modelView;
var mAttribIndex = GL.GetUniformLocation(hProgram, "m");
if (mAttribIndex != -1)
{
GL.UniformMatrix4(mAttribIndex, false, ref M);
}
var MVP = M * projection;
var projAttribIndex = GL.GetUniformLocation(hProgram, "proj");
if (projAttribIndex != -1)
{
GL.UniformMatrix4(projAttribIndex, false, ref MVP);
}
var clrSolid = new Vector4(1, 0, 0, 1);
var clrAttribIndex = GL.GetUniformLocation(hProgram, "oClr");
if (clrAttribIndex != -1)
{
GL.Uniform4(clrAttribIndex, ref clrSolid);
}
//render our model
GL.BindVertexArray(vaoTriangle);
GL.BindBuffer(BufferTarget.ElementArrayBuffer, vboTriangleIndices);
GL.DrawElements(PrimitiveType.Triangles, triangleIndices.Length, DrawElementsType.UnsignedInt, 0);
GL.Enable(EnableCap.Blend);
GL.DepthMask(false);
// Transparent Cube
var rotateZ = Matrix4.CreateRotationZ(alpha);
M = rotateY * rotateZ * modelView;
mAttribIndex = GL.GetUniformLocation(hProgram, "m");
if (mAttribIndex != -1)
{
GL.UniformMatrix4(mAttribIndex, false, ref M);
}
MVP = M * projection;
projAttribIndex = GL.GetUniformLocation(hProgram, "proj");
if (projAttribIndex != -1)
{
GL.UniformMatrix4(projAttribIndex, false, ref MVP);
}
var clrTransparent = new Vector4(0, 1, 0, 0.5f);
clrAttribIndex = GL.GetUniformLocation(hProgram, "oClr");
if (clrAttribIndex != -1)
{
GL.Uniform4(clrAttribIndex, ref clrTransparent);
}
//render our model
GL.BindVertexArray(vaoTriangle);
GL.BindBuffer(BufferTarget.ElementArrayBuffer, vboTriangleIndices);
GL.DrawElements(PrimitiveType.Triangles, triangleIndices.Length, DrawElementsType.UnsignedInt, 0);
GL.DepthMask(true);
//display
w.SwapBuffers();
var error = GL.GetError();
if (error != ErrorCode.NoError)
{
throw new Exception(error.ToString());
}
};
w.Resize += (o, ea) =>
{
GL.Viewport(w.ClientRectangle);
};
w.Run();
}
}