Question

我正在研究一个粒子系统，尽管阅读过所有关于alphas的帖子，但我无法让我的png纹理显示在我的粒子上。

我正在使用SOIL库来读取图像：

void makeTexture () {
    tex_2D = SOIL_load_OGL_single_cubemap(
            "particle2.png",
            SOIL_DDS_CUBEMAP_FACE_ORDER,
            SOIL_LOAD_RGBA,
            SOIL_CREATE_NEW_ID,
            SOIL_FLAG_POWER_OF_TWO
            | SOIL_FLAG_MIPMAPS
            //| SOIL_FLAG_COMPRESS_TO_DXT
            //| SOIL_FLAG_TEXTURE_REPEATS
            //| SOIL_FLAG_INVERT_Y
            | SOIL_FLAG_DDS_LOAD_DIRECT
            );
    if( tex_2D > 0 )
    {
        printf("%s", "2");
        glEnable( GL_TEXTURE_CUBE_MAP );
        glEnable( GL_TEXTURE_GEN_S );
        glEnable( GL_TEXTURE_GEN_T );
        glEnable( GL_TEXTURE_GEN_R );
        glTexGeni( GL_S, GL_TEXTURE_GEN_MODE, GL_REFLECTION_MAP );
        glTexGeni( GL_T, GL_TEXTURE_GEN_MODE, GL_REFLECTION_MAP );
        glTexGeni( GL_R, GL_TEXTURE_GEN_MODE, GL_REFLECTION_MAP );
        glBindTexture( GL_TEXTURE_CUBE_MAP, tex_2D );
    } 
    else
    {
        printf("%s", "3");
        tex_2D = SOIL_load_OGL_HDR_texture(
                "particle2.png",
                SOIL_HDR_RGBE,
                //SOIL_HDR_RGBdivA,
                //SOIL_HDR_RGBdivA2,
                0,
                SOIL_CREATE_NEW_ID,
                SOIL_FLAG_POWER_OF_TWO
                | SOIL_FLAG_MIPMAPS
                //| SOIL_FLAG_COMPRESS_TO_DXT
                );
        if( tex_2D < 1 )
        {
            printf("%s", "4");
            tex_2D = SOIL_load_OGL_texture(
                    "particle2.png",
                    SOIL_LOAD_RGBA,
                    SOIL_CREATE_NEW_ID,
                    SOIL_FLAG_POWER_OF_TWO
                    | SOIL_FLAG_MIPMAPS
                    | SOIL_FLAG_MULTIPLY_ALPHA
                    //| SOIL_FLAG_COMPRESS_TO_DXT
                    | SOIL_FLAG_DDS_LOAD_DIRECT
                    //| SOIL_FLAG_NTSC_SAFE_RGB
                    //| SOIL_FLAG_CoCg_Y
                    //| SOIL_FLAG_TEXTURE_RECTANGLE
                    );
        }

        if( tex_2D > 0 )
        {
            printf("%s", "5");
            glEnable( GL_TEXTURE_2D );
            glBindTexture( GL_TEXTURE_2D, tex_2D );
        } else
        {
            glDisable( GL_TEXTURE_2D );
        }
    }
}

这是我的初始化代码：

void init（void）{

glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glEnable(GL_DEPTH_TEST);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glClearDepth(1.0f);
glDepthFunc(GL_LESS);
glEnable(GL_DEPTH_TEST);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);      
glEnable(GL_BLEND);                     
//glAlphaFunc(GL_GREATER, 0.4);
glEnable(GL_ALPHA_TEST);    
//glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
//glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

glEnable(GL_CULL_FACE);
glCullFace(GL_BACK);

glLoadIdentity();
gluLookAt(0, 0, 5, 0, 0, 0, 0, 1, 0);

glShadeModel (GL_SMOOTH);
glEnable(GL_DEPTH_TEST);
// Enable blending

}

这是我的渲染代码：

void RenderParticles() {
glBegin(GL_POINTS);
    for (int p = 0; p < MAX_PARTICLES; p++) {
        if (Particles[p].Active) {
            glPushMatrix();
            glDepthMask(false);
            float dist = sqrt(pow(Particles[p].X, 2) + pow(Particles[p].Y, 2) + pow(Particles[p].Z, 2));
            glColor4f(Particles[p].R, Particles[p].G, Particles[p].B, 1.0);
            //1.8*(0.5 - dist) + RandomNumber(0, 0.2)
            glBegin(GL_TRIANGLE_STRIP);
            float d = 0.05;
            glTexCoord2d(1,1); glVertex3f(Particles[p].X+d,Particles[p].Y+d,Particles[p].Z); // Top Right
            glTexCoord2d(0,1); glVertex3f(Particles[p].X-d,Particles[p].Y+d,Particles[p].Z); // Top Left
            glTexCoord2d(1,0); glVertex3f(Particles[p].X+d,Particles[p].Y-d,Particles[p].Z); // Bottom Right
            glTexCoord2d(0,0); glVertex3f(Particles[p].X-d,Particles[p].Y-d,Particles[p].Z); // Bottom Left
            glEnd();
            glDepthMask(true);
            //glutSolidSphere(RandomNumber(0.001, 0.002), 20, 20);
            glPopMatrix();
        }
    }
    glEnd();
}

这是我尝试使用的纹理：

Texture

以下是粒子的截图：

particles

Alpha无法在OpenGL中工作

0 个答案: