Hi all! I''ve a problem. You all know the Tutorial with Heightfield Terrain while using a Bitmap-File. I want to make this code better while taking no triangles. I want to bulit the terrain by using Surfaces. I always take 3x3 points which describe my Surface. So, now my problem: When I''m using GL_AUTO_NORMAL the lightning isn''t correct because of all some points use other tangents. How can I make the lightning here correct? I tried it by using my own normals but it didn''t work! Thanks for every help!! greets, Corrail Here my code I''m using: (If you want the whole Source-Code pls Mail me! corrail@gmx.at) /////////////////////// // Terrain Variables // /////////////////////// #define MAPX 31 #define MAPZ 31 #define BitMAPX 32 #define BitMAPZ 32 #define MAPScale 20.0f float terPkt[MAPX][MAPZ][3]; float terAktPkt[3][3][3]; /////////////////////// // InitializeTerrain // /////////////////////// // ImageData is the black-white Image void InitializeTerrain() { for (int i = 0; i < MAPZ; i++) { for (int j = 0; j < MAPX; j++) { terPkt[j][0] = float(i)*MAPScale; terPkt[j][1] = (float)imageData[(j*BitMAPZ+i)*3]; terPkt[j][2] = -float(j)*MAPScale; terNorm[j][0] = 0.0f; terNorm[j][1] = 0.0f; terNorm[j][2] = 0.0f; } } } /////////////////////// // Rendering Terrain // /////////////////////// glFrontFace(GL_CW); for (int a = 0; a < (int)((MAPX-1)/2); a++) { for (int b = 0; b < (int)((MAPZ-1)/2); b++) { for (int c = 0; c < 3; c++) { for (int d = 0; d < 3; d++) { terAktPkt[c][d][0] = terPkt[2*a+c][2*b+d][0]; terAktPkt[c][d][1] = terPkt[2*a+c][2*b+d][1]; terAktPkt[c][d][2] = terPkt[2*a+c][2*b+d][2]; } } glColor3f(1.0,1.0,1.0); glMap2f(GL_MAP2_VERTEX_3, 0.0, count, 3, 3, 0.0, count, 9, 3, &terAktPkt[0][0][0]); glEnable(GL_MAP2_VERTEX_3); glMapGrid2f((int)count, 0.0f, count, (int)count, 0.0f, count); glEvalMesh2(GL_FILL, 0, (int)count, 0, (int)count); } } glFrontFace(GL_CCW); </i>