public void RenderBeforeChildren(RenderEventArgs arg)
{
TransformFeedbackObject tf = transformFeedbackObjects[(currentIndex + 1) % 2];
// update content at (currentIndex + 1)
{
GL.Instance.Enable(GL.GL_RASTERIZER_DISCARD);
RenderMethod method = this.RenderUnit.Methods[currentIndex];
ShaderProgram program = method.Program;
//program.SetUniform("xxx", value);
method.Render(tf); // update buffers and record output to tf's binding.
GL.Instance.Disable(GL.GL_RASTERIZER_DISCARD);
}
// render at (currentIndex + 1)
{
RenderMethod method = this.RenderUnit.Methods[(currentIndex + 1) % 2 + 2];
ShaderProgram program = method.Program;
ICamera camera = arg.Camera;
mat4 projection = camera.GetProjectionMatrix();
mat4 view = camera.GetViewMatrix();
mat4 model = this.GetModelMatrix();
program.SetUniform(mvpMatrix, projection * view * model);
//unit.Render(); // this method must specify vertex count.
tf.Draw(method); // render updated buffers without specifying vertex count.
}
// exchange
{
currentIndex = (currentIndex + 1) % 2;
}
}
protected override void DoInitialize()
{
base.DoInitialize();
for (int i = 0; i < 2; i++)
{
var tf = new TransformFeedbackObject();
RenderMethod method = this.RenderUnit.Methods[i];
VertexShaderAttribute[] attributes = method.VertexArrayObject.VertexAttributes;
for (uint t = 0; t < attributes.Length; t++)
{
tf.BindBuffer(t, attributes[t].Buffer);
}
this.transformFeedbackObjects[i] = tf;
}
}
protected override void DoInitialize()
{
base.DoInitialize();
for (int i = 0; i < 2; i++)
{
var tfo = new TransformFeedbackObject();
RenderMethod method = this.RenderUnit.Methods[i];
VertexArrayObject vao = method.VertexArrayObjects[0]; // only one element here.
VertexShaderAttribute[] attributes = vao.VertexAttributes;
for (uint bindingPointIndex = 0; bindingPointIndex < attributes.Length; bindingPointIndex++)
{
tfo.BindBuffer(bindingPointIndex, attributes[bindingPointIndex].Buffer);
}
this.transformFeedbackObjects[i] = tfo;
}
}
public void RenderBeforeChildren(RenderEventArgs arg)
{
TransformFeedbackObject tfo = transformFeedbackObjects[(currentIndex + 1) % 2];
// update
{
if (this.firstRendering)
{
this.lastTime = DateTime.Now;
this.firstRendering = false;
}
var now = DateTime.Now;
float seconds = (float)now.Subtract(this.lastTime).TotalSeconds;
this.lastTime = now;
GL.Instance.Enable(GL.GL_RASTERIZER_DISCARD);
RenderMethod method = this.RenderUnit.Methods[currentIndex];
ShaderProgram program = method.Program;
// set the uniforms
program.SetUniform("gravity", gravity);
program.SetUniform("deltaTime", seconds);
method.Render(tfo); // update buffers and record output to tf's binding.
GL.Instance.Disable(GL.GL_RASTERIZER_DISCARD);
}
// render
{
RenderMethod method = this.RenderUnit.Methods[(currentIndex + 1) % 2 + 2];
ShaderProgram program = method.Program;
ICamera camera = arg.Camera;
mat4 projection = camera.GetProjectionMatrix();
mat4 view = camera.GetViewMatrix();
mat4 model = this.GetModelMatrix();
program.SetUniform("projectionMat", projection);
program.SetUniform("viewMat", view * model);
//unit.Render(); // this method requires specified vertes count.
tfo.Draw(method); // render updated buffers without specifying vertex count.
}
// exchange
{
currentIndex = (currentIndex + 1) % 2;
}
}
protected override void DoInitialize()
{
base.DoInitialize();
for (int i = 0; i < 2; i++)
{
var tf = new TransformFeedbackObject();
RenderMethod method = this.RenderUnit.Methods[i];
// make sure there is only one vao in this case.
foreach (var vao in method.VertexArrayObjects)
{
VertexShaderAttribute[] attributes = vao.VertexAttributes;
for (uint t = 0; t < attributes.Length; t++)
{
tf.BindBuffer(t, attributes[t].Buffer);
}
}
this.transformFeedbackObjects[i] = tf;
}
}
public override void RenderBeforeChildren(RenderEventArgs arg)
{
TransformFeedbackObject tf = transformFeedbackObjects[(currentIndex + 1) % 2];
// update
{
GL.Instance.Enable(GL.GL_RASTERIZER_DISCARD);
RenderMethod method = this.RenderUnit.Methods[currentIndex];
ShaderProgram program = method.Program;
// set the uniforms
program.SetUniform("center", center);
program.SetUniform("radius", radius);
program.SetUniform("g", g);
program.SetUniform("dt", dt);
program.SetUniform("bounce", bounce);
program.SetUniform("seed", random.Next());
method.Render(ControlMode.ByFrame, tf); // update buffers and record output to tf's binding.
GL.Instance.Disable(GL.GL_RASTERIZER_DISCARD);
}
// render
{
RenderMethod method = this.RenderUnit.Methods[(currentIndex + 1) % 2 + 2];
ShaderProgram program = method.Program;
ICamera camera = arg.CameraStack.Peek();
mat4 projection = camera.GetProjectionMatrix();
mat4 view = camera.GetViewMatrix();
mat4 model = this.GetModelMatrix();
program.SetUniform("Projection", projection);
program.SetUniform("View", view * model);
//unit.Render(); // this methos must specify vertes count.
tf.Draw(method); // render updated buffersi without specifying vertex count.
}
// exchange
{
currentIndex = (currentIndex + 1) % 2;
}
}
public TransformFeedbackCalculator(int maxItemCount)
{
this.MaxItemCount = maxItemCount;
var program = new ShaderProgram();
//program.Initialize(varyings, ShaderProgram.BufferMode.InterLeaved, vertexShader);
var varyings = new string[] { "outValue" };
glTransformFeedbackVaryings(program.ProgramId, varyings.Length, varyings, GL.GL_INTERLEAVED_ATTRIBS);
var vertexShader = new VertexShader(vertexCode);
vertexShader.Initialize();
glAttachShader(program.ProgramId, vertexShader.ShaderId);
glLinkProgram(program.ProgramId);
program.CheckLinkStatus();
VertexBuffer vbo = VertexBuffer.Create(typeof(float), maxItemCount, VBOConfig.Float, BufferUsage.StaticDraw);
var drawCmd = new DrawArraysCmd(DrawMode.Points, maxItemCount);
var vao = new VertexArrayObject(drawCmd, program, new VertexShaderAttribute[] { new VertexShaderAttribute(vbo, "inValue") });
uint index = 0;
VertexBuffer tbo = VertexBuffer.Create(typeof(float), maxItemCount, VBOConfig.Float, BufferUsage.StaticRead);
//glBindBufferBase(GL.GL_TRANSFORM_FEEDBACK_BUFFER, index, tbo.BufferId);
var tfo = new TransformFeedbackObject();
tfo.BindBuffer(index, tbo);
{
this.program = program;
this.inputBuffer = vbo;
this.outputBuffer = tbo;
this.vao = vao;
this.drawCommand = drawCmd;
this.tfo = tfo;
}
}
