Hi,
Ive done a vertex and fragmemnt shader in render monkey. Imported the shade (copy and paste) into a resource file in vs2005 and tried to use it in a very basic way. The Program compiles however the shader doesnt seem to be applied at all.
The shader specic code in the app is:
#define GLEW_STATIC
#include <GL/glew.h>
GLhandleARB v, f, p;
glewInit();
if(GLEW_ARB_vertex_shader && GLEW_ARB_fragment_shader){
v = glCreateShaderObjectARB(GL_VERTEX_SHADER_ARB);
f = glCreateShaderObjectARB(GL_FRAGMENT_SHADER_ARB);
const char *vv = readFile("lambert.vert");
const char *ff = readFile("lambert.frag");
if( vv != NULL && ff != NULL){
glShaderSourceARB(v, 1, &vv, NULL);
glShaderSourceARB(f, 1, &ff, NULL);
glCompileShaderARB(v);
glCompileShaderARB(f);
delete [] vv;
delete [] ff;
p = glCreateProgramObjectARB();
glAttachObjectARB(p, v);
glAttachObjectARB(p, f);
glLinkProgramARB(p);
glUseProgramObjectARB(p);
glUniform1iARB(glGetUniformLocationARB(p, "cloudTexture"), 0);
glUniform4fARB(glGetUniformLocationARB(p, "shaderAmbient"), 1.0f, 0.5f, 0.5f, 1.0f);
glUniform4fARB(glGetUniformLocationARB(p, "shaderDiffuse"), 1.0f, 0.5f, 0.5f, 1.0f);
glUniform3fARB(glGetUniformLocationARB(p, "lightPos"), 25.0f, 50.0f, -15.0f);
}
} In Draw Loop:
glUseProgramObjectARB(p);
glActiveTextureARB(GL_TEXTURE0_ARB);
//Draw Object to be shaded etc
glUseProgramObjectARB(NULL);
//Other Studd using legacy pipelinethe shaders work find in render monkey so its not the actual shaders (i dont think)
frag shader:
uniform vec4 shaderDiffuse;
uniform vec4 shaderAmbient;
//Link from vertex shader holds texture coords
varying vec2 texCoord;
//Link to <-vertexLight
varying vec3 lightDirection;
varying vec3 normal;
//Cloud Texture Access (2d texture)
uniform sampler2D cloudTexture;
void main(void)
{
//Dot Light Direction with normalDirection (Facing Ratio)
//Need to normalise to get value between 0->1 to get different diffuse values
float facingRatio = dot(normalize(normal), normalize(lightDirection));
vec4 diffuseColour = texture2D(cloudTexture,texCoord);
vec4 light1 = (diffuseColour * shaderDiffuse * facingRatio);
gl_FragColor = light1 + (shaderAmbient * diffuseColour);
} vertex shader:
//The Shader works per vertex
//Used to pass through fixed pipeline to fragment shader
varying vec2 texCoord;
varying vec3 normal;
//Artist Tools
uniform vec3 lightPos;
//Light Vector
varying vec3 lightDirection;
void main(void)
{
//Apply fixed pipeline vertex transformations
gl_Position = ftransform();
//Multi texture coordinate for texture 0
texCoord = gl_MultiTexCoord0.xy;
//Get Current Vertex Position (to subtract from lightPos to get the vector)
//Mulitply my modelview to put vetex position into world coordinates
vec4 objectPos = gl_ModelViewMatrix * gl_Vertex;
//Apply the light position into the world space (convert to vec4 w = 1)
//Finds <-vertexLight
lightDirection = (gl_ModelViewMatrix * vec4(lightPos, 1)).xyz - objectPos.xyz;
//Set Model Normals to be pass to fragment shader
normal = gl_NormalMatrix * gl_Normal;
}Im using glew, visualc++ (visual studio 2005)
My gpu supports the latest shaders and gl2.0+
Does something need to be set for glew etc to work in vs2005 or is my code wrong.
Ive set up glew in the linker and in the lib and include sections of vs
Many Thanks For Your help this has been bugging me for a couple of days now
Cheers
-Alex
I am assuming this project compiles fine? No errors? Any errors from GL about the GLSL code? Have you checked to make sure there is no crap at the end of the text files after the last set of brackets?
Grab the output of glGetShaderInfoLog() after compiling and glGetProgramInfoLog() after linking. Those are usually your first stop for shader problems, they have quite verbose output.
I'm not 100% sure but you are using texCoord = gl_MultiTexCoord0.xy; in a way I've not encountered before, in the vertex shader. Not sure if it gets interpolated correctly. Also you're not using OpenGL lighting variables (RenderMonkey really needs to provide support for those, it's a joke not to have them. Bad ATI) but it does seem like you set every variable you needed to for your own lighting.
"Vertex shader failed to compile with the following errors: ERROR: 0:35: '<' : syntax error parse error ERROR: 1 compilation errors. No code generated."
from fragment shader compile:
"Fragment shader failed to compile with the following errors: ERROR: 0:30: '<' : syntax error parse error ERROR: 1 compilation errors. No code generated."
from the linker:
"Vertex and Fragment shader(s) were not successfully compiled before glLinkProgram() was called. Link failed."
so oviously is the shaders not the implementation.
That character only appears in your comments, so I guess it's trying to parse those for some reason... maybe there's a problem with your readFile() routine. Before you go changing it, try testing with simpler shaders, like these ones:
im getting a similar error but with a different number before the '<': "Vertex shader failed to compile with the following errors: ERROR: 0:4: '<' : syntax error parse error ERROR: 1 compilation errors. No code generated."
my read file code is here:
char* readFile(char *fileName){ int fileLength; char *buffer;
