scummvm/graphics/opengl/context.h
2022-06-26 18:32:10 +02:00

128 lines
3.5 KiB
C++

/* 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 3 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, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef GRAPHICS_OPENGL_CONTEXT_H
#define GRAPHICS_OPENGL_CONTEXT_H
#include "common/singleton.h"
namespace OpenGL {
enum ContextType {
kContextNone,
kContextGL,
kContextGLES,
kContextGLES2
};
/**
* Description structure of the OpenGL (ES) context.
*/
class Context : public Common::Singleton<Context> {
public:
Context();
/**
* Initialize the context description from currently active context.
*
* The extensions and features are marked as available according
* to the current context capabilities.
*/
void initialize(ContextType contextType);
/**
* Reset context.
*
* This marks all extensions as unavailable.
*/
void reset();
/** The type of the active context. */
ContextType type;
/** Helper function for checking the GL version supported by the context. */
inline bool isGLVersionOrHigher(int major, int minor) const {
return ((majorVersion > major) || ((majorVersion == major) && (minorVersion >= minor)));
}
/** The GL version supported by the context. */
int majorVersion, minorVersion;
/** The GLSL version supported by the context */
int glslVersion;
/** The maximum texture size supported by the context. */
int maxTextureSize;
/** Whether GL_ARB_texture_non_power_of_two is available or not. */
bool NPOTSupported;
/** Whether shader support is available or not. */
bool shadersSupported;
/** Whether shader support is good enough for engines or not. */
bool enginesShadersSupported;
/** Whether multi texture support is available or not. */
bool multitextureSupported;
/** Whether FBO support is available or not. */
bool framebufferObjectSupported;
/** Whether multisample FBO support is available or not */
bool framebufferObjectMultisampleSupported;
/**
* Contains the maximum number of supported multisample samples
* if multisample FBOs are supported. Contains -1 otherwise.
*/
int multisampleMaxSamples;
/** Whether packed pixels support is available or not. */
bool packedPixelsSupported;
/** Whether packing the depth and stencil buffers is possible or not. */
bool packedDepthStencilSupported;
/** Whether specifying a pitch when uploading to textures is available or not */
bool unpackSubImageSupported;
/** Whether depth component 24 is supported or not */
bool OESDepth24;
/** Whether texture coordinate edge clamping is available or not. */
bool textureEdgeClampSupported;
private:
/**
* Returns the native GLSL version supported by the driver.
* This does NOT take shaders ARB extensions into account.
*/
int getGLSLVersion() const;
};
} // End of namespace OpenGL
/** Shortcut for accessing the active OpenGL context. */
#define OpenGLContext OpenGL::Context::instance()
#endif