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opengltexturesimage-scaling

opengl, textures have always the same size

I'm trying to apply a texture to a vertex array whit the following code:

glEnable(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, texture);
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glColor3f(1.0f, 1.0f, 1.0f);

glEnableClientState(GL_TEXTURE_COORD_ARRAY);
glEnableClientState(GL_VERTEX_ARRAY);
glTexCoordPointer(2, GL_FLOAT, 0, texcoords);
glVertexPointer(3, GL_FLOAT, 0, vertices);
glDrawElements(GL_QUADS, 12, GL_UNSIGNED_BYTE, faceIndices);
glDisableClientState(GL_VERTEX_ARRAY);
glDisableClientState(GL_COLOR_ARRAY);

glDisable(GL_TEXTURE_2D);

with this texture: texture

so i have this result: Result

Now I'm wondering how can I scale the floor texture, i've already tried to scale the texture with photoshop, but the result is the same but heavier.

Solution

  • It depends on your texture coordinates how you want to map the texture. Let take example,it cover the whole polygon

    glTexCoord2f(0.0f, 0.0f);
glTexCoord2f(1.0f, 0.0f);
glTexCoord2f(1.0f, 1.0f);
glTexCoord2f(0.0f, 1.0f);

    Now if you want to repeat the texture five times then provide coordinates like `

    glTexCoord2f(0.0f, 0.0f);
glTexCoord2f(5.0f, 0.0f);
glTexCoord2f(5.0f, 5.0f);
glTexCoord2f(0.0f, 5.0f);`

    Like above example change the value how you want to map the texture.