X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=init.cpp;h=4003163d9494843b3eccc42910ca41084b52a691;hp=f6dd9043751572ec03f4b64dd215ad8e3a217d69;hb=92573f7be18bfca16dd3292cbe536d7d7912198f;hpb=4a55a7fdc6a0e184dda9c19052654989f21163cc diff --git a/init.cpp b/init.cpp index f6dd904..4003163 100644 --- a/init.cpp +++ b/init.cpp @@ -5,22 +5,30 @@ #include #include "init.h" +#include "resource_pool.h" #include "util.h" +using namespace std; + +namespace movit { + bool movit_initialized = false; MovitDebugLevel movit_debug_level = MOVIT_DEBUG_ON; float movit_texel_subpixel_precision; bool movit_srgb_textures_supported; +int movit_num_wrongly_rounded; +bool movit_shader_rounding_supported; // The rules for objects with nontrivial constructors in static scope // are somewhat convoluted, and easy to mess up. We simply have a // pointer instead (and never care to clean it up). -std::string *movit_data_directory = NULL; +string *movit_data_directory = NULL; namespace { void measure_texel_subpixel_precision() { + ResourcePool resource_pool; static const unsigned width = 4096; // Generate a destination texture to render to, and an FBO. @@ -58,8 +66,6 @@ void measure_texel_subpixel_precision() check_error(); glTexImage1D(GL_TEXTURE_1D, 0, GL_LUMINANCE16F_ARB, 2, 0, GL_LUMINANCE, GL_FLOAT, texdata); check_error(); - glEnable(GL_TEXTURE_1D); - check_error(); // Basic state. glDisable(GL_BLEND); @@ -71,36 +77,51 @@ void measure_texel_subpixel_precision() glViewport(0, 0, width, 1); - glMatrixMode(GL_PROJECTION); - glLoadIdentity(); - glOrtho(0.0, 1.0, 0.0, 1.0, 0.0, 1.0); - - glMatrixMode(GL_MODELVIEW); - glLoadIdentity(); + GLuint glsl_program_num = resource_pool.compile_glsl_program( + read_file("vs.vert"), read_file("texture1d.frag")); + glUseProgram(glsl_program_num); + check_error(); + glUniform1i(glGetUniformLocation(glsl_program_num, "tex"), 0); // Bind the 1D sampler. check_error(); // Draw the texture stretched over a long quad, interpolating it out. // Note that since the texel center is in (0.5), we need to adjust the // texture coordinates in order not to get long stretches of (1,1,1,...) // at the start and (...,0,0,0) at the end. - glBegin(GL_QUADS); - - glTexCoord1f(0.25f); - glVertex2f(0.0f, 0.0f); - - glTexCoord1f(0.75f); - glVertex2f(1.0f, 0.0f); - - glTexCoord1f(0.75f); - glVertex2f(1.0f, 1.0f); - - glTexCoord1f(0.25f); - glVertex2f(0.0f, 1.0f); + float vertices[] = { + 0.0f, 0.0f, + 1.0f, 0.0f, + 1.0f, 1.0f, + 0.0f, 1.0f + }; + float texcoords[] = { + 0.25f, 0.0f, + 0.75f, 0.0f, + 0.75f, 0.0f, + 0.25f, 0.0f + }; + + int position_attrib = glGetAttribLocation(glsl_program_num, "position"); + assert(position_attrib != -1); + int texcoord_attrib = glGetAttribLocation(glsl_program_num, "texcoord"); + assert(texcoord_attrib != -1); + glEnableVertexAttribArray(position_attrib); + check_error(); + glVertexAttribPointer(position_attrib, 2, GL_FLOAT, GL_FALSE, 0, vertices); + check_error(); + glEnableVertexAttribArray(texcoord_attrib); + check_error(); + glVertexAttribPointer(texcoord_attrib, 2, GL_FLOAT, GL_FALSE, 0, texcoords); + check_error(); - glEnd(); + glDrawArrays(GL_QUADS, 0, 4); check_error(); - glDisable(GL_TEXTURE_1D); + glUseProgram(0); + check_error(); + glDisableVertexAttribArray(position_attrib); + check_error(); + glDisableVertexAttribArray(texcoord_attrib); check_error(); // Now read the data back and see what the card did. @@ -113,9 +134,10 @@ void measure_texel_subpixel_precision() float biggest_jump = 0.0f; for (unsigned i = 1; i < width; ++i) { assert(out_data[i] >= out_data[i - 1]); - biggest_jump = std::max(biggest_jump, out_data[i] - out_data[i - 1]); + biggest_jump = max(biggest_jump, out_data[i] - out_data[i - 1]); } + assert(biggest_jump > 0.0); movit_texel_subpixel_precision = biggest_jump; // Clean up. @@ -129,52 +151,200 @@ void measure_texel_subpixel_precision() check_error(); glDeleteTextures(1, &src_texnum); check_error(); + + resource_pool.release_glsl_program(glsl_program_num); +} + +void measure_roundoff_problems() +{ + ResourcePool resource_pool; + + // Generate a destination texture to render to, and an FBO. + GLuint dst_texnum, fbo; + + glGenTextures(1, &dst_texnum); + check_error(); + glBindTexture(GL_TEXTURE_2D, dst_texnum); + check_error(); + glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, 512, 1, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL); + check_error(); + + glGenFramebuffers(1, &fbo); + check_error(); + glBindFramebuffer(GL_FRAMEBUFFER, fbo); + check_error(); + glFramebufferTexture2D( + GL_FRAMEBUFFER, + GL_COLOR_ATTACHMENT0, + GL_TEXTURE_2D, + dst_texnum, + 0); + check_error(); + + // Now generate a texture where every value except the last should be + // rounded up to the next one. However, there are cards (in highly + // common use) that can't do this right, for unknown reasons. + GLuint src_texnum; + float texdata[512]; + for (int i = 0; i < 256; ++i) { + texdata[i * 2 + 0] = (i + 0.48) / 255.0; + texdata[i * 2 + 1] = (i + 0.52) / 255.0; + } + glGenTextures(1, &src_texnum); + check_error(); + glBindTexture(GL_TEXTURE_1D, src_texnum); + check_error(); + glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); + check_error(); + glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); + check_error(); + glTexImage1D(GL_TEXTURE_1D, 0, GL_LUMINANCE32F_ARB, 512, 0, GL_LUMINANCE, GL_FLOAT, texdata); + check_error(); + + // Basic state. + glDisable(GL_BLEND); + check_error(); + glDisable(GL_DEPTH_TEST); + check_error(); + glDepthMask(GL_FALSE); + check_error(); + + glViewport(0, 0, 512, 1); + + GLuint glsl_program_num = resource_pool.compile_glsl_program( + read_file("vs.vert"), read_file("texture1d.frag")); + glUseProgram(glsl_program_num); + check_error(); + glUniform1i(glGetUniformLocation(glsl_program_num, "tex"), 0); // Bind the 1D sampler. + + // Draw the texture stretched over a long quad, interpolating it out. + float vertices[] = { + 0.0f, 0.0f, + 1.0f, 0.0f, + 1.0f, 1.0f, + 0.0f, 1.0f + }; + float texcoords[] = { + 0.25f, 0.0f, + 0.75f, 0.0f, + 0.75f, 0.0f, + 0.25f, 0.0f + }; + int position_attrib = glGetAttribLocation(glsl_program_num, "position"); + assert(position_attrib != -1); + int texcoord_attrib = glGetAttribLocation(glsl_program_num, "texcoord"); + assert(texcoord_attrib != -1); + glEnableVertexAttribArray(position_attrib); + check_error(); + glVertexAttribPointer(position_attrib, 2, GL_FLOAT, GL_FALSE, 0, vertices); + check_error(); + glEnableVertexAttribArray(texcoord_attrib); + check_error(); + glVertexAttribPointer(texcoord_attrib, 2, GL_FLOAT, GL_FALSE, 0, texcoords); + check_error(); + glDrawArrays(GL_QUADS, 0, 4); + + glUseProgram(0); + check_error(); + glDisableVertexAttribArray(position_attrib); + check_error(); + glDisableVertexAttribArray(texcoord_attrib); + + // Now read the data back and see what the card did. (Ignore the last value.) + // (We only look at the red channel; the others will surely be the same.) + unsigned char out_data[512]; + glReadPixels(0, 0, 512, 1, GL_RED, GL_UNSIGNED_BYTE, out_data); + check_error(); + + int wrongly_rounded = 0; + for (unsigned i = 0; i < 255; ++i) { + if (out_data[i * 2 + 0] != i) { + ++wrongly_rounded; + } + if (out_data[i * 2 + 1] != i + 1) { + ++wrongly_rounded; + } + } + + movit_num_wrongly_rounded = wrongly_rounded; + + // Clean up. + glBindTexture(GL_TEXTURE_1D, 0); + check_error(); + glBindFramebuffer(GL_FRAMEBUFFER, 0); + check_error(); + glDeleteFramebuffers(1, &fbo); + check_error(); + glDeleteTextures(1, &dst_texnum); + check_error(); + glDeleteTextures(1, &src_texnum); + check_error(); + + resource_pool.release_glsl_program(glsl_program_num); } -void check_extensions() +bool check_extensions() { // We fundamentally need FBOs and floating-point textures. - assert(glewIsSupported("GL_ARB_framebuffer_object") != 0); - assert(glewIsSupported("GL_ARB_texture_float") != 0); + if (!glewIsSupported("GL_ARB_framebuffer_object")) return false; + if (!glewIsSupported("GL_ARB_texture_float")) return false; // We assume that we can use non-power-of-two textures without restrictions. - assert(glewIsSupported("GL_ARB_texture_non_power_of_two") != 0); + if (!glewIsSupported("GL_ARB_texture_non_power_of_two")) return false; // We also need GLSL fragment shaders. - assert(glewIsSupported("GL_ARB_fragment_shader") != 0); - assert(glewIsSupported("GL_ARB_shading_language_100") != 0); + if (!glewIsSupported("GL_ARB_fragment_shader")) return false; + if (!glewIsSupported("GL_ARB_shading_language_100")) return false; // FlatInput and YCbCrInput uses PBOs. (They could in theory do without, // but no modern card would really not provide it.) - assert(glewIsSupported("GL_ARB_pixel_buffer_object") != 0); + if (!glewIsSupported("GL_ARB_pixel_buffer_object")) return false; // ResampleEffect uses RG textures to encode a two-component LUT. - assert(glewIsSupported("GL_ARB_texture_rg") != 0); + if (!glewIsSupported("GL_ARB_texture_rg")) return false; // sRGB texture decode would be nice, but are not mandatory // (GammaExpansionEffect can do the same thing if needed). movit_srgb_textures_supported = glewIsSupported("GL_EXT_texture_sRGB"); + + // We may want to use round() at the end of the final shader, + // if supported. We need either GLSL 1.30 or this extension to do that, + // and 1.30 brings with it other things that we don't want to demand + // for now. + movit_shader_rounding_supported = glewIsSupported("GL_EXT_gpu_shader4"); + + return true; } } // namespace -void init_movit(const std::string& data_directory, MovitDebugLevel debug_level) +bool init_movit(const string& data_directory, MovitDebugLevel debug_level) { if (movit_initialized) { - return; + return true; } - movit_data_directory = new std::string(data_directory); + movit_data_directory = new string(data_directory); movit_debug_level = debug_level; - glewInit(); + GLenum err = glewInit(); + if (err != GLEW_OK) { + return false; + } // geez glPixelStorei(GL_PACK_ALIGNMENT, 1); glPixelStorei(GL_UNPACK_ALIGNMENT, 1); + glDisable(GL_DITHER); + if (!check_extensions()) { + return false; + } measure_texel_subpixel_precision(); - check_extensions(); + measure_roundoff_problems(); movit_initialized = true; + return true; } + +} // namespace movit