gpu/gl/GrGLContext.h

/*
 * Copyright 2013 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */


#ifndef GrGLContext_DEFINED
#define GrGLContext_DEFINED

#include "gl/GrGLExtensions.h"
#include "gl/GrGLInterface.h"
#include "GrGLCaps.h"
#include "GrGLSL.h"
#include "GrGLUtil.h"

#include "SkString.h"

/**
 * Encapsulates information about an OpenGL context including the OpenGL
 * version, the GrGLBinding type of the context, and GLSL version.
 */
class GrGLContextInfo {
public:
    /**
     * Default constructor
     */
    GrGLContextInfo() {
        fGLCaps.reset(SkNEW(GrGLCaps));
        this->reset();
    }

    /**
     * Copies a GrGLContextInfo
     */
    GrGLContextInfo& operator= (const GrGLContextInfo& ctxInfo);

    /**
     * Initializes a GrGLContextInfo from a GrGLInterface and the currently
     * bound OpenGL context accessible by the GrGLInterface.
     */
    bool initialize(const GrGLInterface* interface);
    bool isInitialized() const;

    GrGLBinding binding() const { return fBindingInUse; }
    GrGLVersion version() const { return fGLVersion; }
    GrGLSLGeneration glslGeneration() const { return fGLSLGeneration; }
    GrGLVendor vendor() const { return fVendor; }
    GrGLRenderer renderer() const { return fRenderer; }
    /** Is this a mesa-based driver. Does not mean it is the osmesa software rasterizer. */
    bool isMesa() const { return fIsMesa; }
    /** Are we running inside Chromium (using the command buffer)? We make some different tradeoffs
        about what errors to check for because queries are synchronous. We should probably expose
        this as an option for clients other than Chromium. */
    bool isChromium() const { return fIsChromium; }
    const GrGLCaps* caps() const { return fGLCaps.get(); }
    GrGLCaps* caps() { return fGLCaps; }
    const GrGLExtensions& extensions() const { return fExtensions; }

    /**
     * Shortcut for extensions().has(ext);
     */
    bool hasExtension(const char* ext) const {
        if (!this->isInitialized()) {
            return false;
        }
        return fExtensions.has(ext);
    }

    /**
     * Reset the information
     */
    void reset();

private:

    GrGLBinding             fBindingInUse;
    GrGLVersion             fGLVersion;
    GrGLSLGeneration        fGLSLGeneration;
    GrGLVendor              fVendor;
    GrGLRenderer            fRenderer;
    GrGLExtensions          fExtensions;
    bool                    fIsMesa;
    bool                    fIsChromium;
    SkAutoTUnref<GrGLCaps>  fGLCaps;
};

/**
 * Encapsulates the GrGLInterface used to make GL calls plus information
 * about the context (via GrGLContextInfo).
 */
class GrGLContext {
public:
    /**
     * Default constructor
     */
    GrGLContext() { this->reset(); }

    /**
     * Creates a GrGLContext from a GrGLInterface and the currently
     * bound OpenGL context accessible by the GrGLInterface.
     */
    explicit GrGLContext(const GrGLInterface* interface);

    /**
     * Copies a GrGLContext
     */
    GrGLContext(const GrGLContext& ctx);

    ~GrGLContext() { SkSafeUnref(fInterface); }

    /**
     * Copies a GrGLContext
     */
    GrGLContext& operator= (const GrGLContext& ctx);

    /**
     * Initializes a GrGLContext from a GrGLInterface and the currently
     * bound OpenGL context accessible by the GrGLInterface.
     */
    bool initialize(const GrGLInterface* interface);
    bool isInitialized() const { return fInfo.isInitialized(); }

    const GrGLInterface* interface() const { return fInterface; }
    const GrGLContextInfo& info() const { return fInfo; }
    GrGLContextInfo& info() { return fInfo; }

private:
    void reset();

    const GrGLInterface* fInterface;
    GrGLContextInfo      fInfo;
};

#endif