If I use fog with setShaderAuto(), I get the following error:
Shader Generator does not support Fog yet.
How can I mix the fog with other effect that need the default shaders ?
You can perhaps write a custom shader that provides the combination of features you need. The auto-shader generator, after all, is simply generating a shader that you could have written directly.
David
A workaround would be to let the auto shader generate a shader, grab it, print it out, add your fog code, and then use it as custom shader.
Thank you. Looks like shader is a must learn topic.
Hi pro-rsoft
After I grab the shader:
sg = ShaderGenerator.getDefault()
shader = sg.synthesizeShader(render.getState()).getShader()
text=shader.getText()
Is it usually that I have to modify it case by case ? Or in general I can make a generic fog shader to integrate with generated shader ?
The shader generated by Panda handles many attributes. If I am not going to make a shader generator, does it mean that I have to make very specific shader for my particular requirement (say a uniform Fog).
Uh, yes. Whenever you add a light or so, the shader has to be re-generated.
I grab the shader from the normal mapping tutorial in runtime by:
sg = ShaderGenerator.getDefault()
shader = sg.synthesizeShader(render.getState()).getShader()
text=shader.getText()
The shader I get is like this:
//Cg
void vshader(
in float4 vtx_color : COLOR,
out float4 l_color : COLOR,
uniform float4x4 trans_model_to_view,
uniform float4x4 tpose_view_to_model,
in float4 vtx_normal : TEXCOORD0,
out float4 l_normal : TEXCOORD1,
out float4 l_pos : TEXCOORD0,
float4 vtx_position : POSITION,
out float4 l_position : POSITION,
uniform float4x4 mat_modelproj
) {
l_position = mul(mat_modelproj, vtx_position);
l_color = vtx_color;
l_pos = mul(trans_model_to_view, vtx_position);
l_normal.xyz = mul((float3x3)tpose_view_to_model, vtx_normal.xyz);
l_normal.w = 0;
}
void fshader(
in float3 l_normal : TEXCOORD1,
in float4 l_pos : TEXCOORD0,
uniform float4 alight_alight0,
uniform float4x4 plight_plight0_rel_view,
out float4 o_color : COLOR0,
in float4 l_color : COLOR
) {
float4 result;
// Fetch all textures.
// Correct the surface normal for interpolation effects
l_normal = normalize(l_normal);
// Begin view-space light calculations
float ldist,lattenv,langle;
float4 lcolor,lspec,lvec,lpoint,latten,ldir,leye,lhalf;
float4 tot_ambient = float4(0,0,0,0);
float4 tot_diffuse = float4(0,0,0,0);
// Ambient Light 0
lcolor = alight_alight0;
tot_ambient += lcolor;
// Point Light 0
lcolor = plight_plight0_rel_view[0];
lspec = plight_plight0_rel_view[1];
lpoint = plight_plight0_rel_view[2];
latten = plight_plight0_rel_view[3];
lvec = lpoint - l_pos;
ldist = length(float3(lvec));
lvec /= ldist;
lattenv = 1/(latten.x + latten.y*ldist + latten.z*ldist*ldist);
lcolor *= lattenv * saturate(dot(l_normal, lvec.xyz));
tot_diffuse += lcolor;
// Begin view-space light summation
result = float4(0,0,0,0);
result += tot_ambient * l_color;
result += tot_diffuse * l_color;
result = saturate(result);
// End view-space light calculations
o_color = result * 1.000001;
}The shader seems only taking care of the lights but not the texture. Why ?
[/code]
Maybe because “render” didn’t have any textures applied?
There is only one model under render. If I grab the shader from the abstract room node, the shader program is even short !
Only call it for the actual node which has the texture. You can check which one that is by calling render.ls().
Hi pro-rsoft,
I’ve made a scene graph navigator and walk through all nodes in the scene graph to grab the auto shader text generated by panda. So far I still not able to get a correct shader from any of the node.
Do you have any small working example ?
Hmm, not really. But there must be some node which has the render state with the generated shader applied.
I do more tests and have some findings and questions:
Do a render.ls()
PandaNode render S:(CullFaceAttrib LightAttrib RenderModeAttrib RescaleNormalAtt
rib ShaderAttrib)
PandaNode camera T:m(pos 58.1848 -58.8497 19.8081 hpr 39.6 2.2 0)
Camera cam (PerspectiveLens)
PerspectiveLens fov = 39.3201 30
ModelRoot abstractroom.egg
PandaNode
GeomNode polySurface2 (3 geoms: TextureAttrib)I thought that the TextureAttrib shall be at GeomNode polySurface 2. But it is not.
I can get it at that geom node by calling getGeomState(0)
Thus the render state for the auto shader at that geomnode shall be:
geomnodepath.getNetState() + geomnode.getGeomState(0)
?
Since it is possible for getGeomState return different states for different geoms in this geom node, does it mean that the autoshader will generate a different shader for each geom in that geomnode instead of just one shader for one geomnode ?
Hmm, I think it should be either gnp.getNetState() or gnp.getNetState().compose(gn.getGeomState(n)). I don’t know.
Thank you for your help. It can produce something useful with the new code. Looks like it need to compute the net state for each Geom under each Geom node.