FXACE

No problem.




Which shader version you need? (1.0 is enough?)

Did you have the algorithm to load shaders?

//vertex shader

void main()

{

 gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;

 gl_TexCoord[0].xy = gl_MultiTexCoord0.xy;
}


// fragment/pixel shader

uniform sampler2D firstGrassTexture;

uniform sampler2D secondGrassTexture;

uniform sampler2D maskTexture;

void main()

{

 gl_FragColor = mix(texture2D(firstGrassTexture,gl_TexCoord[0].xy), texture2D(secondGrassTexture,gl_TexCoord[0].xy), texture2D(maskTexture,gl_TexCoord[0].xy).a); 
}

you need to do this in your application:

GLhadleARB shaderProgram; // somewhere defined in your application (of course it must be loaded)

glUseProgramObjectARB(shaderProgram);

glUniform1iARB(glGetUniformLocationARB(shaderProgram,"firstGrassTexture"),0);

glUniform1iARB(glGetUniformLocationARB(shaderProgram,"secondGrassTexture"),1);

glUniform1iARB(glGetUniformLocationARB(shaderProgram,"maskTexture"),2);

glUseProgramObjectARB(0);

The code which was introduced above is a initialization of uniforms setup (so, just call it once).

The next code you need to call each time when you render your object with this shader:

glActiveTextureARB(GL_TEXTURE0_ARB);

glBindTexture(...);// here you bind first grass texture

glActiveTextureARB(GL_TEXTURE1_ARB);

glBindTexture(...);// here you bind second grass texture

glActiveTextureARB(GL_TEXTURE2_ARB);

glBindTexture(...);// here you bind mask texture

glActiveTextureARB(GL_TEXTURE0_ARB);

glUseProgramObjectARB(shaderProgram);




Draw the mesh




glUseProgramObjectARB(0);// disable using shader (maybe you have some object below which you want to draw them without using shaders

Best wishes, FXACE.

use glBindAttibLocation with specified value which you want before calling glLinkProgram.

And then should be ok.




Best wishes, FXACE.

gl_FragColor = mix(FirstTextureColor, SecondTextureColor, coeff);

Where:

FirstTextureColor is a color returned by texture2D(<first texture>,...);

SecondTextureColor is a color returned by texture2D(<second texture>,...);

coeff -> X% of second texture and (100 - X)% of first texture.




Best wishes, FXACE.

glEnable(GL_TEXTURE_2D) - checked.

glTexCoord (before each glVertex call) - nowhere. <<

-------------------------------------------------------------------

glEnable(GL_DEPTH_TEST) - you enabled depth testing but you never cleaning it (depth buffer).

------------------------------------------------------------------

glOrtho(100,100,100,100,100,100) - bad usage of matrix setup (are you trying to render a single point?)

your primitive never would be projected into screen with this matrix.




As the results, you seeing white screen because you set clear color to white color (and nothing other would be drawn).

So, first of all, you need to to create function pointers of GL extensions:

PFNGLCREATEPROGRAMOBJECTARBPROC glCreateProgramObjectARB;

PFNGLCREATESHADEROBJECTARBPROC glCreateShaderObjectARB;

Next stage is to receive pointers to these functions by glGetProcAddress, for example:

glCreateProgramObjectARB=(PFNGLCREATEPROGRAMOBJECTARBPROC)glGetProcAddress("glCreateProgramObjectARB");

...

Note that glGetProcAddress works only after initialized GL context....

There are many references and tutorials out of there.... For example: http://www.codesampl...er_simple_vs2ps

-me

Is problem not solved if you use this line:

#include <windows.h>

before

#include <GL/glut.h>

?