問題描述
GLSL和HLSL之間的模型視圖區別？ (Modelview Difference between GLSL and HLSL?)
I'm wondering if there is a difference between GLSL and HLSL Mathematics. I'm using a selfmade Engine which works with openTK fine. My SharpDx Implementation gets everyday a bit further. I'm currently working on the ModelviewProjection Matrix. To see if it works I use a simple project which works fine with OpenTK. So I changed the Shader code from GLSL to HLSL because the rest of the program uses the engine functions. The programm did not work I couldn't see the geometry, so I changed the Modelview Matrix and the Projections Matrix to the Identity Matrix. Aftwards it worked I saw the geometry. So I changed a bit of the GLSL becuase I wanted a similar GLSL code to the HLSL and I also changed the Matrixes to the identy too. Afterwards I did not see anything it didn't work.... So I'm stuck... Any of you have an Idea? Anyways long story short My HLSL Shader Code
public string Vs = @"cbuffer Variables : register(b0){
float4 Testfarbe;
float4x4 FUSEE_MVP;
}
struct VS_IN
{
float4 pos : POSITION;
float4 tex : TEXCOORD;
float4 normal : NORMAL;
};
struct PS_IN
{
float4 pos : SV_POSITION;
float4 col : COLOR;
float4 tex : TEXCOORD;
float4 normal : NORMAL;
};
PS_IN VS( VS_IN input )
{
PS_IN output = (PS_IN)0;
input.pos.w = 1.0f;
output.pos = mul(input.pos,FUSEE_MVP);
output.col = Testfarbe;
/*output.col = FUSEE_MV._m00_m01_m02_m03;*/
/* output.normal = input.normal;
output.tex = input.tex;*/
/* if (FUSEE_MV._m00 == 4.0f)
output.col = float4(1,0,0,1);
else
output.col = float4(0,0,1,1);*/
return output;
}
";
string Ps = @"
SamplerState pictureSampler;
Texture2D imageFG;
struct PS_IN
{
float4 pos : SV_POSITION;
float4 col : COLOR;
float4 tex : TEXCOORD;
float4 normal : NORMAL;
};
float4 PS( PS_IN input ) : SV_Target
{
return input.col;
/*return imageFG.Sample(pictureSampler,input.tex);*/
}";
So I changed my old working OpenTk project to see where the difference ist between openTK and SharpDx relating to the math calculations.
The HLSL code
public string Vs = @"
/* Copies incoming vertex color without change.
* Applies the transformation matrix to vertex position.
*/
attribute vec4 fuColor;
attribute vec3 fuVertex;
attribute vec3 fuNormal;
attribute vec2 fuUV;
varying vec4 vColor;
varying vec3 vNormal;
varying vec2 vUV;
uniform mat4 FUSEE_MVP;
uniform mat4 FUSEE_ITMV;
void main()
{
gl_Position = FUSEE_MVP * vec4(fuVertex, 1.0);
/*vNormal = mat3(FUSEE_ITMV[0].xyz, FUSEE_ITMV[1].xyz, FUSEE_ITMV[2].xyz) * fuNormal;*/
vUV = fuUV;
}";
public string Ps = @"
/* Copies incoming fragment color without change. */
#ifdef GL_ES
precision highp float;
#endif
uniform vec4 vColor;
varying vec3 vNormal;
void main()
{
gl_FragColor = vColor * dot(vNormal, vec3(0, 0, 1));
}";
In the main code itself I only read an Obj file and set the Identity matrix
public override void Init()
{
Mesh = MeshReader.LoadMesh(@"Assets/Teapot.obj.model");
//ShaderProgram sp = RC.CreateShader(Vs, Ps);
sp = RC.CreateShader(Vs, Ps);
_vTextureParam = sp.GetShaderParam("Testfarbe");//vColor
}
public override void RenderAFrame()
{
... var mtxRot = float4x4.CreateRotationY(_angleHorz) * float4x4.CreateRotationX(_angleVert); var mtxCam = float4x4.LookAt(0, 200, 500, 0, 0, 0, 0, 1, 0);
// first mesh
RC.ModelView = float4x4.CreateTranslation(0, ‑50, 0) * mtxRot * float4x4.CreateTranslation(‑150, 0, 0) * mtxCam;
RC.SetShader(sp);
//mapping
RC.SetShaderParam(_vTextureParam, new float4(0.0f, 1.0f, 0.0f, 1.0f));
RC.Render(Mesh);
Present();
}
public override void Resize()
{
RC.Viewport(0, 0, Width, Height);
float aspectRatio = Width / (float)Height;
RC.Projection = float4x4.CreatePerspectiveFieldOfView(MathHelper.PiOver4, aspectRatio, 1, 5000);
}
The both programs side by side
What I should also add is as soon as the values of my ModelView identity are bigger than 1.5 I don't see anything in my window ? anyone knows that might causing this?
I edited the Post and the Image so you see a bigger difference. I had earlier in this post the identity Matrix. If I use the Identity Matrix with this Obj‑File
v 0.0 0.5 0.5
v 0.5 0.0 0.5
v ‑0.5 0.0 0.5
vt 1 0 0
vt 0 1 0
vt 0 0 0
f 1/2 2/3 3/1
I saw in my SharpDX project the triangle and in my openTK not. But I tink the Teapot thing is a bit better to show the difference within the to project where only the Shadercode is different! I mean I could've done something wrong in the SharpDX Implementation for this Enginge but lets assume their is everything right. At least I hope so if you guys tell my the ShaderCode is just wrong ;)
I hope I could describe my problem clear so you understand it.
參考解法
方法 1:
OK So you've to Transpose the Matrix...