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FatalError
03-17-2001, 07:30 AM
Hi !
I have a problem with selection buffer.

I'm drawing a grid of rectangles but when I click on the grid Opengl sets the number of hits to 1 and the number of the object hit is always 0

Here's the code:

void Mouse3D(int mouseX,int mouseY,Vector& v1,Vector& v2)
{
GLuint selectBuff[64];
GLint hits, viewport[4];

glSelectBuffer(64, selectBuff);
glGetIntegerv(GL_VIEWPORT, viewport);

glMatrixMode(GL_PROJECTION);
glPushMatrix();
glRenderMode(GL_SELECT);
glLoadIdentity();
gluPickMatrix(mouseX, viewport[3]-mouseY, 2, 2, viewport);

gluPerspective(45.0f,(GLfloat)800/(GLfloat)600,1.0f,1000.0f);
glMatrixMode(GL_MODELVIEW);
camera.Set();

bf.DrawCases();

hits = glRenderMode(GL_RENDER);

if(hits > 0)
index = selectBuff[3];

glMatrixMode(GL_PROJECTION);

glPopMatrix();
glMatrixMode(GL_MODELVIEW);
}

bf.drawCases draws the grid. Each rectangle has one different color and one name with LoadName(numRect);

Thanks

zed
03-17-2001, 02:10 PM
selection has to be done just right to work try looking at some sample code eg the red book , or in glut, also my site has an example (url in profile)