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Diffstat (limited to 'backends/graphics/opengl/context.cpp')
| -rw-r--r-- | backends/graphics/opengl/context.cpp | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/backends/graphics/opengl/context.cpp b/backends/graphics/opengl/context.cpp new file mode 100644 index 0000000000..a7f640d37e --- /dev/null +++ b/backends/graphics/opengl/context.cpp @@ -0,0 +1,182 @@ +/* ScummVM - Graphic Adventure Engine + * + * ScummVM is the legal property of its developers, whose names + * are too numerous to list here. Please refer to the COPYRIGHT + * file distributed with this source distribution. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + */ + +#include "backends/graphics/opengl/opengl-sys.h" +#include "backends/graphics/opengl/opengl-graphics.h" +#include "backends/graphics/opengl/shader.h" +#include "backends/graphics/opengl/pipelines/pipeline.h" +#include "backends/graphics/opengl/framebuffer.h" + +#include "common/tokenizer.h" +#include "common/debug.h" + +namespace OpenGL { + +void Context::reset() { + maxTextureSize = 0; + + NPOTSupported = false; + shadersSupported = false; + multitextureSupported = false; + framebufferObjectSupported = false; + +#define GL_FUNC_DEF(ret, name, param) name = nullptr; +#include "backends/graphics/opengl/opengl-func.h" +#undef GL_FUNC_DEF + + activePipeline = nullptr; +} + +Pipeline *Context::setPipeline(Pipeline *pipeline) { + Pipeline *oldPipeline = activePipeline; + if (oldPipeline) { + oldPipeline->deactivate(); + } + + activePipeline = pipeline; + if (activePipeline) { + activePipeline->activate(); + } + + return oldPipeline; +} + +Context g_context; + +void OpenGLGraphicsManager::setContextType(ContextType type) { +#if USE_FORCED_GL + type = kContextGL; +#elif USE_FORCED_GLES + type = kContextGLES; +#elif USE_FORCED_GLES2 + type = kContextGLES2; +#endif + + g_context.type = type; +} + +void OpenGLGraphicsManager::initializeGLContext() { + // Initialize default state. + g_context.reset(); + + // Load all functions. + // We use horrible trickery to silence C++ compilers. + // See backends/plugins/sdl/sdl-provider.cpp for more information. + assert(sizeof(void (*)()) == sizeof(void *)); + void *fn = nullptr; + +#define LOAD_FUNC(name, loadName) \ + fn = getProcAddress(#loadName); \ + memcpy(&g_context.name, &fn, sizeof(fn)) + +#define GL_EXT_FUNC_DEF(ret, name, param) LOAD_FUNC(name, name) + +#ifdef USE_BUILTIN_OPENGL +#define GL_FUNC_DEF(ret, name, param) g_context.name = &name +#define GL_FUNC_2_DEF GL_FUNC_DEF +#else +#define GL_FUNC_DEF GL_EXT_FUNC_DEF +#define GL_FUNC_2_DEF(ret, name, extName, param) \ + if (g_context.type == kContextGL) { \ + LOAD_FUNC(name, extName); \ + } else { \ + LOAD_FUNC(name, name); \ + } +#endif +#include "backends/graphics/opengl/opengl-func.h" +#undef GL_FUNC_2_DEF +#undef GL_FUNC_DEF +#undef GL_EXT_FUNC_DEF +#undef LOAD_FUNC + + // Obtain maximum texture size. + GL_CALL(glGetIntegerv(GL_MAX_TEXTURE_SIZE, &g_context.maxTextureSize)); + debug(5, "OpenGL maximum texture size: %d", g_context.maxTextureSize); + + const char *extString = (const char *)g_context.glGetString(GL_EXTENSIONS); + debug(5, "OpenGL extensions: %s", extString); + + bool ARBShaderObjects = false; + bool ARBShadingLanguage100 = false; + bool ARBVertexShader = false; + bool ARBFragmentShader = false; + + Common::StringTokenizer tokenizer(extString, " "); + while (!tokenizer.empty()) { + Common::String token = tokenizer.nextToken(); + + if (token == "GL_ARB_texture_non_power_of_two" || token == "GL_OES_texture_npot") { + g_context.NPOTSupported = true; + } else if (token == "GL_ARB_shader_objects") { + ARBShaderObjects = true; + } else if (token == "GL_ARB_shading_language_100") { + ARBShadingLanguage100 = true; + } else if (token == "GL_ARB_vertex_shader") { + ARBVertexShader = true; + } else if (token == "GL_ARB_fragment_shader") { + ARBFragmentShader = true; + } else if (token == "GL_ARB_multitexture") { + g_context.multitextureSupported = true; + } else if (token == "GL_EXT_framebuffer_object") { + g_context.framebufferObjectSupported = true; + } + } + + if (g_context.type == kContextGLES2) { + // GLES2 always has (limited) NPOT support. + g_context.NPOTSupported = true; + + // GLES2 always has shader support. + g_context.shadersSupported = true; + + // GLES2 always has multi texture support. + g_context.multitextureSupported = true; + + // GLES2 always has FBO support. + g_context.framebufferObjectSupported = true; + } else { + g_context.shadersSupported = ARBShaderObjects & ARBShadingLanguage100 & ARBVertexShader & ARBFragmentShader; + } + + // Log context type. + switch (g_context.type) { + case kContextGL: + debug(5, "OpenGL: GL context initialized"); + break; + + case kContextGLES: + debug(5, "OpenGL: GLES context initialized"); + break; + + case kContextGLES2: + debug(5, "OpenGL: GLES2 context initialized"); + break; + } + + // Log features supported by GL context. + debug(5, "OpenGL: NPOT texture support: %d", g_context.NPOTSupported); + debug(5, "OpenGL: Shader support: %d", g_context.shadersSupported); + debug(5, "OpenGL: Multitexture support: %d", g_context.multitextureSupported); + debug(5, "OpenGL: FBO support: %d", g_context.framebufferObjectSupported); +} + +} // End of namespace OpenGL |