Le problème vient bien de là ?
tessellator.startDrawingQuads();
tessellator.addVertexWithUV((double)((float)(b0 + 0) + f), (double)((float)(b1 + 128) - f), -0.009999999776482582D, 0.0D, 1.0D);
tessellator.addVertexWithUV((double)((float)(b0 + 128) - f), (double)((float)(b1 + 128) - f), -0.009999999776482582D, 1.0D, 1.0D);
tessellator.addVertexWithUV((double)((float)(b0 + 128) - f), (double)((float)(b1 + 0) + f), -0.009999999776482582D, 1.0D, 0.0D);
tessellator.addVertexWithUV((double)((float)(b0 + 0) + f), (double)((float)(b1 + 0) + f), -0.009999999776482582D, 0.0D, 0.0D);
tessellator.draw();
Pour tester mets en commentaire par exemple