I am trying to add a particle system to my game engine, but it''s not going so well. I am using TGAs for the textures on particles, but the texture does not seem to be applied. Here''s my code: void CBubbles::Render() { // enable alpha blending and texturing glEnable(GL_BLEND); glEnable(GL_TEXTURE_2D); glDepthMask(GL_FALSE); // set the blend mode glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); glEnable(GL_ALPHA_TEST); glAlphaFunc(GL_GREATER, 0); // get modelview matrix float mat[16]; glGetFloatv(GL_MODELVIEW_MATRIX, mat); // for billboarding CVector right(mat[0], mat[4], mat[8]); CVector up(mat[1], mat[5], mat[9]); // select the bubble texture glBindTexture(GL_TEXTURE_2D, m_texture); glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE); // to avoid constant dereferecning... CVector partPos; float size; glColor4f(1.0f, 0.5f, 0.0f, 1.0f); // draw the quads glBegin(GL_QUADS); for(int i = 0; i < m_numParticles; ++i) { partPos = m_particleList.m_pos; size = m_particleList.m_size; glTexCoord2f(0.0, 0.0); glVertex3fv((partPos + (right + up) * -size).array); glTexCoord2f(1.0, 0.0); glVertex3fv((partPos + (right - up) * size).array); glTexCoord2f(0.0, 1.0); glVertex3fv((partPos + (right + up) * size).array); glTexCoord2f(1.0, 1.0); glVertex3fv((partPos + (up - right) * size).array); } glEnd(); glDisable(GL_BLEND); glDisable(GL_ALPHA); glDisable(GL_TEXTURE_2D); glDepthMask(GL_TRUE); } The texture for this part of the particle system is a blank tga that just has an alpha channel. This code worked in another example program i made, but now its failing. When I run the code, I just get colored quads, instead of quads with an alpha blended quads. The texture isnt being applied. Can someone help me out? Thanks. </i>

// get modelview matrix
float mat[16];
glGetFloatv(GL_MODELVIEW_MATRIX, mat);

I get the matrix once per frame, just after camera positioning, for billboarding and camera movements.


glBindTexture(GL_TEXTURE_2D, m_texture);

How sure are you that the texture loaded?



glTexCoord2f(0.0, 0.0); glVertex3fv((partPos + (right + up) * -size).array);
glTexCoord2f(1.0, 0.0); glVertex3fv((partPos + (right - up) * size).array);
glTexCoord2f(0.0, 1.0); glVertex3fv((partPos + (right + up) * size).array);
glTexCoord2f(1.0, 1.0); glVertex3fv((partPos + (up - right) * size).array);


Is there a reason why you are drawing the quad texcoords in a Z shape vs a box?



The texture for this part of the particle system is a blank tga that just has an alpha channel.

what do you mean by blank? Is this why there is no texture? in modulate mode the final frag color is glcolor*texcolor.


This code
worked in another example program i made, but now its failing. When I run the code, I just get colored
quads, instead of quads with an alpha blended quads. The texture isnt being applied.


What if you loaded a real image w/ rgb and a?

zin

zintel.com - 3d graphics & more or less

By blank I mean just white. I think someething is messing up the binding of the texture. I know the texture is being loaded. As for the Z pattern of texturing that was a mistake I made, but the alpha problem still exists. Heres the code for loading the texture:

Texture texture;
bool tgaFileToLoad = TRUE; // toggle TGA or BMP
// get a texture object
glGenTextures(1, &m_texture);
glBindTexture(GL_TEXTURE_2D, m_texture); // enables the texture object.
// the following fucntions affect the
// texture specified by the 2nd parameter

if (tgaFileToLoad)
{


LoadTGA(&texture, "sparky.tga");

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);

//MessageBox(NULL, "Texture is Loaded", "Textures",MB_OK | MB_ICONEXCLAMATION);

gluBuild2DMipmaps(GL_TEXTURE_2D, 4, texture.width, texture.height, GL_RGBA, GL_UNSIGNED_BYTE, texture.imageData);

// we''re done with the TGA data
free(texture.imageData);


I think something else in my program is messing up my binding or something. What kind of commands could cause conflicts?

I found the problem. Thanks