Hello all! Today i dived into GLSL for first time, so sorry if i write something stupid.
One user at #radeon (nick <papillon81>) asked why some shade doesn't work. Here is link to vertex shader as i saw it today: http://mapserver.flightgear.org/git/gitweb.pl?p=fgdata;a=blob;f=Shaders/3dcloud.vert;h=135658ddb12c83e0652c85181f92575eeb06cf50;hb=HEAD With unmodified Mesa master (after commit what enabled OpenGL 2.1/GLSL 1.20 for r600 in master) there was error: ------------------ Compiling VERTEX source: 1: // -*-C++-*- 2: #version 120 3: 4: varying float fogFactor; 5: 6: attribute vec3 usrAttr1; 7: attribute vec3 usrAttr2; 8: 9: float textureIndexX = usrAttr1.r; 10: float textureIndexY = usrAttr1.g; 11: float wScale = usrAttr1.b; 12: float hScale = usrAttr2.r; 13: float shade = usrAttr2.g; 14: float cloud_height = usrAttr2.b; 15: 16: void main(void) 17: { 18: gl_TexCoord[0] = gl_MultiTexCoord0 + vec4(textureIndexX, textureIndexY, 0.0, 0.0); 19: vec4 ep = gl_ModelViewMatrixInverse * vec4(0.0,0.0,0.0,1.0); 20: vec4 l = gl_ModelViewMatrixInverse * vec4(0.0,0.0,1.0,1.0); 21: vec3 u = normalize(ep.xyz - l.xyz); 22: 23: // Find a rotation matrix that rotates 1,0,0 into u. u, r and w are 24: // the columns of that matrix. 25: vec3 absu = abs(u); 26: vec3 r = normalize(vec3(-u.y, u.x, 0)); 27: vec3 w = cross(u, r); 28: 29: // Do the matrix multiplication by [ u r w pos]. Assume no 30: // scaling in the homogeneous component of pos. 31: gl_Position = vec4(0.0, 0.0, 0.0, 1.0); 32: gl_Position.xyz = gl_Vertex.x * u; 33: gl_Position.xyz += gl_Vertex.y * r * wScale; 34: gl_Position.xyz += gl_Vertex.z * w * hScale; 35: gl_Position.xyz += gl_Color.xyz; 36: 37: // Determine a lighting normal based on the vertex position from the 38: // center of the cloud, so that sprite on the opposite side of the cloud to the sun are darker. 39: float n = dot(normalize(-gl_LightSource[0].position.xyz), 40: normalize(mat3x3(gl_ModelViewMatrix) * (- gl_Position.xyz)));; 41: 42: // Determine the position - used for fog and shading calculations 43: vec3 ecPosition = vec3(gl_ModelViewMatrix * gl_Position); 44: float fogCoord = abs(ecPosition.z); 45: float fract = smoothstep(0.0, cloud_height, gl_Position.z + cloud_height); 46: 47: // Final position of the sprite 48: gl_Position = gl_ModelViewProjectionMatrix * gl_Position; 49: 50: // Determine the shading of the sprite based on its vertical position and position relative to the sun. 51: n = min(smoothstep(-0.5, 0.0, n), fract); 52: // Determine the shading based on a mixture from the backlight to the front 53: vec4 backlight = gl_LightSource[0].diffuse * shade; 54: 55: gl_FrontColor = mix(backlight, gl_LightSource[0].diffuse, n); 56: gl_FrontColor += gl_FrontLightModelProduct.sceneColor; 57: 58: // As we get within 100m of the sprite, it is faded out. Equally at large distances it also fades out. 59: gl_FrontColor.a = min(smoothstep(10.0, 100.0, fogCoord), 1 - smoothstep(15000.0, 20000.0, fogCoord)); 60: gl_BackColor = gl_FrontColor; 61: 62: // Fog doesn't affect clouds as much as other objects. 63: fogFactor = exp( -gl_Fog.density * fogCoord * 0.5); 64: fogFactor = clamp(fogFactor, 0.0, 1.0); 65: } VERTEX glCompileShader "" FAILED VERTEX Shader "" infolog: Error: mat3x3: undeclared function name. Compiling FRAGMENT source: 1: uniform sampler2D baseTexture; 2: varying float fogFactor; 3: 4: void main(void) 5: { 6: vec4 base = texture2D( baseTexture, gl_TexCoord[0].st); 7: vec4 finalColor = base * gl_Color; 8: gl_FragColor.rgb = mix(gl_Fog.color.rgb, finalColor.rgb, fogFactor ); 9: gl_FragColor.a = mix(0.0, finalColor.a, fogFactor); 10: } 11: Linking osg::Program "" id=29 contextID=0 Program's vertex attrib binding 10, usrAttr1 Program's vertex attrib binding 11, usrAttr2 glLinkProgram "" FAILED Program "" infolog: linking with uncompiled shader --------------------------------- so, we dived in and found few links with some similar-looking problems. Topic at Flightgear forum: http://www.flightgear.org/forums/viewtopic.php?f=6&t=2387&p=77851 Message in Mac-OpenGL list: http://lists.apple.com/archives/mac-opengl/2010/Aug/msg00000.html vdrift developer's forum: http://vdrift.net/Forum/viewtopic.php?t=734 And finally after modifying shader it compiles sucessfully: we changed line 40 from normalize(mat3x3(gl_ModelViewMatrix) * (- gl_Position.xyz)));; into normalize(vec3(gl_ModelViewMatrix * vec4(- gl_Position.xyz,0.0))));; i tried to make simple patch, but it FAIL with real testing. Patch was simple: ------------------------ diff --git a/src/mesa/slang/slang_typeinfo.c b/src/mesa/slang/slang_typeinfo.c index d039a12..847e330 100644 --- a/src/mesa/slang/slang_typeinfo.c +++ b/src/mesa/slang/slang_typeinfo.c @@ -187,8 +187,11 @@ static const type_specifier_type_name type_specifier_type_names[] = { {"vec3", SLANG_SPEC_VEC3}, {"vec4", SLANG_SPEC_VEC4}, {"mat2", SLANG_SPEC_MAT2}, + {"mat2x2", SLANG_SPEC_MAT2}, {"mat3", SLANG_SPEC_MAT3}, + {"mat3x3", SLANG_SPEC_MAT3}, {"mat4", SLANG_SPEC_MAT4}, + {"mat4x4", SLANG_SPEC_MAT4}, {"mat2x3", SLANG_SPEC_MAT23}, {"mat3x2", SLANG_SPEC_MAT32}, {"mat2x4", SLANG_SPEC_MAT24}, as GLSL spec says on page 20: "mat3x3 same as a mat3" - http://www.opengl.org/registry/doc/GLSLangSpec.Full.1.20.8.pdf But because my patch fail - i guess i need add new type into slang_typeinfo.h and then modify slang_typeinfo.c with completely new type (for other matNxN [square] cases too). I understand all work now focused on glsl2 branch, but may be our work (if i produce anything working) will be useful for 7.8 ? _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
