src/libGLESv2/Context.h

//
// Copyright (c) 2002-2014 The ANGLE Project Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//

// Context.h: Defines the gl::Context class, managing all GL state and performing
// rendering operations. It is the GLES2 specific implementation of EGLContext.

#ifndef LIBGLESV2_CONTEXT_H_
#define LIBGLESV2_CONTEXT_H_

#include "angle_gl.h"
#include <EGL/egl.h>

#include <string>
#include <set>
#include <map>
#include <unordered_map>
#include <array>

#include "common/angleutils.h"
#include "common/RefCountObject.h"
#include "libGLESv2/Caps.h"
#include "libGLESv2/Error.h"
#include "libGLESv2/HandleAllocator.h"
#include "libGLESv2/angletypes.h"
#include "libGLESv2/Constants.h"
#include "libGLESv2/VertexAttribute.h"
#include "libGLESv2/State.h"

namespace rx
{
class Renderer;
}

namespace egl
{
class Surface;
}

namespace gl
{
class Shader;
class Program;
class ProgramBinary;
class Texture;
class Texture2D;
class TextureCubeMap;
class Texture3D;
class Texture2DArray;
class Framebuffer;
class Renderbuffer;
class RenderbufferStorage;
class Colorbuffer;
class Depthbuffer;
class Stencilbuffer;
class DepthStencilbuffer;
class FenceNV;
class FenceSync;
class Query;
class ResourceManager;
class Buffer;
struct VertexAttribute;
class VertexArray;
class Sampler;
class TransformFeedback;

class Context
{
  public:
    Context(int clientVersion, const gl::Context *shareContext, rx::Renderer *renderer, bool notifyResets, bool robustAccess);

    virtual ~Context();

    void makeCurrent(egl::Surface *surface);

    virtual void markContextLost();
    bool isContextLost();

    // These create  and destroy methods are merely pass-throughs to 
    // ResourceManager, which owns these object types
    GLuint createBuffer();
    GLuint createShader(GLenum type);
    GLuint createProgram();
    GLuint createTexture();
    GLuint createRenderbuffer();
    GLuint createSampler();
    GLuint createTransformFeedback();
    GLsync createFenceSync(GLenum condition);

    void deleteBuffer(GLuint buffer);
    void deleteShader(GLuint shader);
    void deleteProgram(GLuint program);
    void deleteTexture(GLuint texture);
    void deleteRenderbuffer(GLuint renderbuffer);
    void deleteSampler(GLuint sampler);
    void deleteTransformFeedback(GLuint transformFeedback);
    void deleteFenceSync(GLsync fenceSync);

    // Framebuffers are owned by the Context, so these methods do not pass through
    GLuint createFramebuffer();
    void deleteFramebuffer(GLuint framebuffer);

    // NV Fences are owned by the Context.
    GLuint createFenceNV();
    void deleteFenceNV(GLuint fence);
    
    // Queries are owned by the Context;
    GLuint createQuery();
    void deleteQuery(GLuint query);

    // Vertex arrays are owned by the Context
    GLuint createVertexArray();
    void deleteVertexArray(GLuint vertexArray);

    void bindArrayBuffer(GLuint buffer);
    void bindElementArrayBuffer(GLuint buffer);
    void bindTexture2D(GLuint texture);
    void bindTextureCubeMap(GLuint texture);
    void bindTexture3D(GLuint texture);
    void bindTexture2DArray(GLuint texture);
    void bindReadFramebuffer(GLuint framebuffer);
    void bindDrawFramebuffer(GLuint framebuffer);
    void bindRenderbuffer(GLuint renderbuffer);
    void bindVertexArray(GLuint vertexArray);
    void bindSampler(GLuint textureUnit, GLuint sampler);
    void bindGenericUniformBuffer(GLuint buffer);
    void bindIndexedUniformBuffer(GLuint buffer, GLuint index, GLintptr offset, GLsizeiptr size);
    void bindGenericTransformFeedbackBuffer(GLuint buffer);
    void bindIndexedTransformFeedbackBuffer(GLuint buffer, GLuint index, GLintptr offset, GLsizeiptr size);
    void bindCopyReadBuffer(GLuint buffer);
    void bindCopyWriteBuffer(GLuint buffer);
    void bindPixelPackBuffer(GLuint buffer);
    void bindPixelUnpackBuffer(GLuint buffer);
    void useProgram(GLuint program);
    void linkProgram(GLuint program);
    void setProgramBinary(GLuint program, GLenum binaryFormat, const void *binary, GLint length);
    void bindTransformFeedback(GLuint transformFeedback);

    void beginQuery(GLenum target, GLuint query);
    void endQuery(GLenum target);

    void setFramebufferZero(Framebuffer *framebuffer);

    void setRenderbufferStorage(GLsizei width, GLsizei height, GLenum internalformat, GLsizei samples);

    void setVertexAttribDivisor(GLuint index, GLuint divisor);

    void samplerParameteri(GLuint sampler, GLenum pname, GLint param);
    void samplerParameterf(GLuint sampler, GLenum pname, GLfloat param);
    GLint getSamplerParameteri(GLuint sampler, GLenum pname);
    GLfloat getSamplerParameterf(GLuint sampler, GLenum pname);

    Buffer *getBuffer(GLuint handle);
    FenceNV *getFenceNV(GLuint handle);
    FenceSync *getFenceSync(GLsync handle) const;
    Shader *getShader(GLuint handle) const;
    Program *getProgram(GLuint handle) const;
    Texture *getTexture(GLuint handle) const;
    Framebuffer *getFramebuffer(GLuint handle) const;
    Renderbuffer *getRenderbuffer(GLuint handle);
    VertexArray *getVertexArray(GLuint handle) const;
    Sampler *getSampler(GLuint handle) const;
    Query *getQuery(GLuint handle, bool create, GLenum type);
    TransformFeedback *getTransformFeedback(GLuint handle) const;

    Texture *getTargetTexture(GLenum target) const;
    Texture2D *getTexture2D() const;
    TextureCubeMap *getTextureCubeMap() const;
    Texture3D *getTexture3D() const;
    Texture2DArray *getTexture2DArray() const;

    Texture *getSamplerTexture(unsigned int sampler, TextureType type) const;

    bool isSampler(GLuint samplerName) const;

    void getBooleanv(GLenum pname, GLboolean *params);
    void getFloatv(GLenum pname, GLfloat *params);
    void getIntegerv(GLenum pname, GLint *params);
    void getInteger64v(GLenum pname, GLint64 *params);

    bool getIndexedIntegerv(GLenum target, GLuint index, GLint *data);
    bool getIndexedInteger64v(GLenum target, GLuint index, GLint64 *data);

    bool getQueryParameterInfo(GLenum pname, GLenum *type, unsigned int *numParams);
    bool getIndexedQueryParameterInfo(GLenum target, GLenum *type, unsigned int *numParams);

    void clear(GLbitfield mask);
    void clearBufferfv(GLenum buffer, int drawbuffer, const float *values);
    void clearBufferuiv(GLenum buffer, int drawbuffer, const unsigned int *values);
    void clearBufferiv(GLenum buffer, int drawbuffer, const int *values);
    void clearBufferfi(GLenum buffer, int drawbuffer, float depth, int stencil);

    void readPixels(GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, GLsizei *bufSize, void* pixels);
    void drawArrays(GLenum mode, GLint first, GLsizei count, GLsizei instances);
    void drawElements(GLenum mode, GLsizei count, GLenum type,
                      const GLvoid *indices, GLsizei instances,
                      const rx::RangeUI &indexRange);
    void sync(bool block);   // flush/finish

    void recordError(const Error &error);

    GLenum getError();
    GLenum getResetStatus();
    virtual bool isResetNotificationEnabled();

    virtual int getClientVersion() const;

    const Caps &getCaps() const;
    const TextureCapsMap &getTextureCaps() const;
    const Extensions &getExtensions() const;

    unsigned int getMaximumCombinedTextureImageUnits() const;
    unsigned int getMaximumCombinedUniformBufferBindings() const;
    unsigned int getMaxTransformFeedbackBufferBindings() const;
    GLintptr getUniformBufferOffsetAlignment() const;
    const std::string &getRendererString() const;

    const std::string &getExtensionString() const;
    const std::string &getExtensionString(size_t idx) const;
    size_t getExtensionStringCount() const;

    void getCurrentReadFormatType(GLenum *internalFormat, GLenum *format, GLenum *type);

    void blitFramebuffer(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1, GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                         GLbitfield mask, GLenum filter);

    void invalidateFrameBuffer(GLenum target, GLsizei numAttachments, const GLenum* attachments,
                               GLint x, GLint y, GLsizei width, GLsizei height);

    rx::Renderer *getRenderer() { return mRenderer; }

    State &getState() { return mState; }
    const State &getState() const { return mState; }

  private:
    DISALLOW_COPY_AND_ASSIGN(Context);

    // TODO: std::array may become unavailable using older versions of GCC
    typedef std::array<unsigned int, IMPLEMENTATION_MAX_FRAMEBUFFER_ATTACHMENTS> FramebufferTextureSerialArray;

    bool applyRenderTarget(GLenum drawMode, bool ignoreViewport);
    void applyState(GLenum drawMode);
    void applyShaders(ProgramBinary *programBinary, bool transformFeedbackActive);
    void applyTextures(SamplerType shaderType, Texture *textures[], TextureType *textureTypes, SamplerState *samplers,
                       size_t textureCount, const FramebufferTextureSerialArray& framebufferSerials,
                       size_t framebufferSerialCount);
    bool applyUniformBuffers();
    bool applyTransformFeedbackBuffers();
    void markTransformFeedbackUsage();

    void detachBuffer(GLuint buffer);
    void detachTexture(GLuint texture);
    void detachFramebuffer(GLuint framebuffer);
    void detachRenderbuffer(GLuint renderbuffer);
    void detachVertexArray(GLuint vertexArray);
    void detachTransformFeedback(GLuint transformFeedback);
    void detachSampler(GLuint sampler);

    void generateSwizzles(Texture *textures[], size_t count);
    size_t getCurrentTexturesAndSamplerStates(ProgramBinary *programBinary, SamplerType type, Texture **outTextures,
                                              TextureType *outTextureTypes, SamplerState *outSamplers);
    Texture *getIncompleteTexture(TextureType type);

    bool skipDraw(GLenum drawMode);

    void initRendererString();
    void initExtensionStrings();

    size_t getBoundFramebufferTextureSerials(FramebufferTextureSerialArray *outSerialArray);

    void initCaps(GLuint clientVersion);

    // Caps to use for validation
    Caps mCaps;
    TextureCapsMap mTextureCaps;
    Extensions mExtensions;

    rx::Renderer *const mRenderer;
    State mState;

    int mClientVersion;

    BindingPointer<Texture2D> mTexture2DZero;
    BindingPointer<TextureCubeMap> mTextureCubeMapZero;
    BindingPointer<Texture3D> mTexture3DZero;
    BindingPointer<Texture2DArray> mTexture2DArrayZero;

    typedef std::unordered_map<GLuint, Framebuffer*> FramebufferMap;
    FramebufferMap mFramebufferMap;
    HandleAllocator mFramebufferHandleAllocator;

    typedef std::unordered_map<GLuint, FenceNV*> FenceNVMap;
    FenceNVMap mFenceNVMap;
    HandleAllocator mFenceNVHandleAllocator;

    typedef std::unordered_map<GLuint, Query*> QueryMap;
    QueryMap mQueryMap;
    HandleAllocator mQueryHandleAllocator;

    typedef std::unordered_map<GLuint, VertexArray*> VertexArrayMap;
    VertexArrayMap mVertexArrayMap;
    HandleAllocator mVertexArrayHandleAllocator;

    BindingPointer<TransformFeedback> mTransformFeedbackZero;
    typedef std::unordered_map<GLuint, TransformFeedback*> TransformFeedbackMap;
    TransformFeedbackMap mTransformFeedbackMap;
    HandleAllocator mTransformFeedbackAllocator;

    std::string mRendererString;
    std::string mExtensionString;
    std::vector<std::string> mExtensionStrings;

    BindingPointer<Texture> mIncompleteTextures[TEXTURE_TYPE_COUNT];

    // Recorded errors
    typedef std::set<GLenum> ErrorSet;
    ErrorSet mErrors;

    // Current/lost context flags
    bool mHasBeenCurrent;
    bool mContextLost;
    GLenum mResetStatus;
    GLenum mResetStrategy;
    bool mRobustAccess;

    ResourceManager *mResourceManager;
};
}

#endif   // INCLUDE_CONTEXT_H_