<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>It's a vtkTextActor, using the vtkOpenGLFreeTypeTextMapper.</div><div><br></div><div>It's not related to the OpenGL extensions in my opinion, but it's related to the creation of this RGBA texture, before sending it to the OpenGL pipeline.</div><div><br></div><div>Here are the OpenGL extensions:</div><div><br></div><div><div>ATI Radeon X1900 OpenGL Engine<span class="Apple-tab-span" style="white-space:pre"> </span></div><div>Vendor Name <span class="Apple-tab-span" style="white-space:pre"> </span>ATI Technologies Inc.</div><div>Version <span class="Apple-tab-span" style="white-space:pre"> </span>2.0 ATI-1.5.24</div><div>GL Shading Language Version <span class="Apple-tab-span" style="white-space:pre"> </span>1.20</div><div>Renderer Name <span class="Apple-tab-span" style="white-space:pre"> </span>ATI Radeon X1900 OpenGL Engine</div><div>OpenGL Extensions <span class="Apple-tab-span" style="white-space:pre"> </span></div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_aux_depth_stencil</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_client_storage</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_element_array</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_fence</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_float_pixels</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_flush_buffer_range</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_flush_render</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_object_purgeable</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_packed_pixels</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_pixel_buffer</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_specular_vector</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_texture_range</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_transform_hint</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_vertex_array_object</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_vertex_array_range</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_vertex_program_evaluators</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_APPLE_ycbcr_422</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_depth_texture</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_draw_buffers</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_fragment_program</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_fragment_program_shadow</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_fragment_shader</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_half_float_pixel</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_imaging</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_multisample</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_multitexture</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_occlusion_query</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_pixel_buffer_object</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_point_parameters</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_point_sprite</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_shader_objects</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_shader_texture_lod</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_shading_language_100</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_shadow</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_shadow_ambient</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_texture_border_clamp</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_texture_compression</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_texture_cube_map</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_texture_env_add</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_texture_env_combine</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_texture_env_crossbar</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_texture_env_dot3</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_texture_float</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_texture_mirrored_repeat</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_texture_non_power_of_two</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_texture_rectangle</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_transpose_matrix</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_vertex_blend</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_vertex_buffer_object</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_vertex_program</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_vertex_shader</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ARB_window_pos</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ATI_blend_equation_separate</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ATI_blend_weighted_minmax</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ATI_separate_stencil</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ATI_text_fragment_shader</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ATI_texture_compression_3dc</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ATI_texture_env_combine3</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ATI_texture_float</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_ATI_texture_mirror_once</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_abgr</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_bgra</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_blend_color</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_blend_equation_separate</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_blend_func_separate</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_blend_minmax</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_blend_subtract</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_clip_volume_hint</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_compiled_vertex_array</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_draw_range_elements</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_fog_coord</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_framebuffer_blit</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_framebuffer_multisample</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_framebuffer_object</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_geometry_shader4</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_gpu_program_parameters</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_multi_draw_arrays</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_packed_depth_stencil</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_rescale_normal</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_secondary_color</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_separate_specular_color</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_shadow_funcs</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_stencil_two_side</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_stencil_wrap</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_texture_compression_dxt1</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_texture_compression_s3tc</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_texture_env_add</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_texture_filter_anisotropic</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_texture_lod_bias</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_texture_mirror_clamp</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_texture_rectangle</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_texture_sRGB</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_EXT_transform_feedback</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_IBM_rasterpos_clip</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_NV_blend_square</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_NV_fog_distance</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_NV_light_max_exponent</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_NV_texgen_reflection</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_SGIS_generate_mipmap</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_SGIS_texture_edge_clamp</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_SGIS_texture_lod</div><div> <span class="Apple-tab-span" style="white-space:pre"> </span>GL_SGI_color_matrix</div><div>OpenGL Limits <span class="Apple-tab-span" style="white-space:pre"> </span></div><div>Display Mask <span class="Apple-tab-span" style="white-space:pre"> </span>1 (0x00000001)</div><div>Renderer ID <span class="Apple-tab-span" style="white-space:pre"> </span>137476 (0x00021904)</div><div>Off Screen <span class="Apple-tab-span" style="white-space:pre"> </span>No</div><div>Full Screen <span class="Apple-tab-span" style="white-space:pre"> </span>Yes</div><div>Hardware Accelerated <span class="Apple-tab-span" style="white-space:pre"> </span>Yes</div><div>Robust <span class="Apple-tab-span" style="white-space:pre"> </span>No</div><div>Backing Store <span class="Apple-tab-span" style="white-space:pre"> </span>Yes</div><div>MP Safe <span class="Apple-tab-span" style="white-space:pre"> </span>Yes</div><div>Window <span class="Apple-tab-span" style="white-space:pre"> </span>Yes</div><div>Multi Screen <span class="Apple-tab-span" style="white-space:pre"> </span>No</div><div>Compliant <span class="Apple-tab-span" style="white-space:pre"> </span>Yes</div><div>Buffer Modes <span class="Apple-tab-span" style="white-space:pre"> </span>15 (0x0000000f)</div><div>Color Buffer Modes <span class="Apple-tab-span" style="white-space:pre"> </span>176194560 (0x0a808400)</div><div>Accum Buffer Modes <span class="Apple-tab-span" style="white-space:pre"> </span>8421376 (0x00808000)</div><div>Depth Buffer Modes <span class="Apple-tab-span" style="white-space:pre"> </span>7169 (0x00001c01)</div><div>Stencil Buffer Modes <span class="Apple-tab-span" style="white-space:pre"> </span>129 (0x00000081)</div><div>Max Aux Buffers <span class="Apple-tab-span" style="white-space:pre"> </span>2 (0x00000002)</div><div>Max Sample Buffers <span class="Apple-tab-span" style="white-space:pre"> </span>1 (0x00000001)</div><div>Max Samples <span class="Apple-tab-span" style="white-space:pre"> </span>6 (0x00000006)</div><div>Sample Modes <span class="Apple-tab-span" style="white-space:pre"> </span>3 (0x00000003)</div><div>Alpha Sampling <span class="Apple-tab-span" style="white-space:pre"> </span>Yes</div><div>GPU Vertex Processing Capable <span class="Apple-tab-span" style="white-space:pre"> </span>Yes</div><div>GPU Fragment Processing Capable<span class="Apple-tab-span" style="white-space:pre"> </span>Yes</div><div>Total Video Memory <span class="Apple-tab-span" style="white-space:pre"> </span>536870912 (0x20000000)</div><div>Total Texture Memory <span class="Apple-tab-span" style="white-space:pre"> </span>519766016 (0x1efb0000)</div><div>Apple Software Renderer <span class="Apple-tab-span" style="white-space:pre"> </span></div><div><br></div></div><div><br></div><div><br></div><div><html>On 6 avr. 08, at 18:00, <a href="mailto:vtkusers-request@vtk.org">vtkusers-request@vtk.org</a> wrote:</html><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; ">Message: 8<br>Date: Sun, 6 Apr 2008 09:11:35 -0400<br>From: "Francois Bertel" <<a href="mailto:francois.bertel@kitware.com">francois.bertel@kitware.com</a>><br>Subject: Re: [vtkusers] Bug in font rendering if shadow == true ?<br>To:<span class="Apple-converted-space"> </span><a href="mailto:vtkusers@vtk.org">vtkusers@vtk.org</a><br>Message-ID:<br><span class="Apple-tab-span" style="white-space: pre; "> </span><<a href="mailto:d9819a910804060611t1aab2a3cwd10d008c400cd15d@mail.gmail.com">d9819a910804060611t1aab2a3cwd10d008c400cd15d@mail.gmail.com</a>><br>Content-Type: text/plain; charset=ISO-8859-1<br><br>Hi Antoine,<br><br>Which class are you using to display the text given by your<br>screenshot? In other words, which class is using vtkFreeTypeUtilities<br>underneath in your case?<br>There are several of them using vtkFreeTypeUtilities:<br>vtkOpenGLFreeTypeTextMapper, vtkTextActor, vtkTextActor3D,<br>vtkTextRepresentation, vtkCaptionRepresentation.<br><br>It sounds like an issue with pre-multiplied rgb with an associated<br>alpha vs rgb which an unassociated alpha.<br><br>Can you send your OpenGL version and set of extensions, either by<br>sending the output of:<br>$ ctest -R LoadOpenGLExtension -V &> output.txt<br><br>or by using a platform specific method:<br><a href="http://www.vtk.org/Wiki/VTK_FAQ#How_do_I_check_which_OpenGL_versions_or_extensions_are_supported_by_my_graphic_card_or_OpenGL_implementation.3F">http://www.vtk.org/Wiki/VTK_FAQ#How_do_I_check_which_OpenGL_versions_or_extensions_are_supported_by_my_graphic_card_or_OpenGL_implementation.3F</a><br></span></blockquote></div><br></body></html>