我在顶点着色器中有一条线
gl_Position = gl_ModelViewProjectionMatrix * vertex;
我需要在没有着色器的情况下进行相同的计算,例如:
float vertex[4];
float modelviewProjection[16];
glGetFloatv(GL_MODELVIEW_MATRIX, modelviewProjection);
glMatrixMode(GL_PROJECTION_MATRIX);
glMultMatrixf(modelviewProjection);
for ( counter = 0; counter < numPoints; counter++ )
{
vertex[0] = *vertexPointer + randomAdvance(timeAlive) + sin(ParticleTime);
vertex[1] = *( vertexPointer + 1 ) + randomAdvance(timeAlive) + timeAlive * 0.6f;
vertex[2] = *( vertexPointer + 2 );
glPushMatrix();
glMultMatrixf(vertex);
*vertexPointer = vertex[0];
*( vertexPointer + 1 ) = vertex[1];
*( vertexPointer + 2 ) = vertex[2];
vertexPointer += 3;
glPopMatrix();
}