gpu/src/win/GrGLDefaultInterface_win.cpp

/*
 * Copyright 2011 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */


#include "GrGLInterface.h"

#include <Windows.h>
#include <GL/GL.h>

/*
 * Windows makes the GL funcs all be __stdcall instead of __cdecl :(
 * This implementation will only work if GR_GL_FUNCTION_TYPE is __stdcall.
 * Otherwise, a springboard would be needed that hides the calling convention.
 */

#define GR_GL_GET_PROC(F) gDefaultInterface.f ## F = (GrGL ## F ## Proc) wglGetProcAddress("gl" #F);
#define GR_GL_GET_PROC_SUFFIX(F, S) gDefaultInterface.f ## F = (GrGL ## F ## Proc) wglGetProcAddress("gl" #F #S);

void GrGLSetDefaultGLInterface() {
    static GrGLInterface gDefaultInterface;
    static bool gDefaultInterfaceInit;
    if (!gDefaultInterfaceInit) {

        // wglGetProcAddress requires a context.
        if (NULL != wglGetCurrentContext()) {
            int major, minor;
            const char* versionString = (const char*) glGetString(GL_VERSION);
            const char* extString = (const char*) glGetString(GL_EXTENSIONS);
            gl_version_from_string(&major, &minor, versionString);

            if (major == 1 && minor < 5) {
                // We must have array and element_array buffer objects.
                return;
            }

            gDefaultInterface.fNPOTRenderTargetSupport = kProbe_GrGLCapability;
            gDefaultInterface.fMinRenderTargetHeight = kProbe_GrGLCapability;
            gDefaultInterface.fMinRenderTargetWidth = kProbe_GrGLCapability;

            // Functions that are part of GL 1.1 will return NULL in
            // wglGetProcAddress
            gDefaultInterface.fBlendFunc = glBlendFunc;
            gDefaultInterface.fClear = glClear;
            gDefaultInterface.fClearColor = glClearColor;
            gDefaultInterface.fClearStencil = glClearStencil;
            gDefaultInterface.fColor4ub = glColor4ub;
            gDefaultInterface.fColorMask = glColorMask;
            gDefaultInterface.fColorPointer = glColorPointer;
            gDefaultInterface.fCullFace = glCullFace;
            gDefaultInterface.fDeleteTextures = glDeleteTextures;
            gDefaultInterface.fDepthMask = glDepthMask;
            gDefaultInterface.fDisable = glDisable;
            gDefaultInterface.fDisableClientState = glDisableClientState;
            gDefaultInterface.fDrawArrays = glDrawArrays;
            gDefaultInterface.fDrawBuffer = glDrawBuffer;
            gDefaultInterface.fDrawElements = glDrawElements;
            gDefaultInterface.fEnable = glEnable;
            gDefaultInterface.fEnableClientState = glEnableClientState;
            gDefaultInterface.fFrontFace = glFrontFace;
            gDefaultInterface.fGenTextures = glGenTextures;
            gDefaultInterface.fGetError = glGetError;
            gDefaultInterface.fGetIntegerv = glGetIntegerv;
            gDefaultInterface.fGetString = glGetString;
            gDefaultInterface.fGetTexLevelParameteriv = glGetTexLevelParameteriv;
            gDefaultInterface.fLineWidth = glLineWidth;
            gDefaultInterface.fLoadMatrixf = glLoadMatrixf;
            gDefaultInterface.fMatrixMode = glMatrixMode;
            gDefaultInterface.fPixelStorei = glPixelStorei;
            gDefaultInterface.fPointSize = glPointSize;
            gDefaultInterface.fReadPixels = glReadPixels;
            gDefaultInterface.fScissor = glScissor;
            gDefaultInterface.fShadeModel = glShadeModel;
            gDefaultInterface.fStencilFunc = glStencilFunc;
            gDefaultInterface.fStencilMask = glStencilMask;
            gDefaultInterface.fStencilOp = glStencilOp;
            gDefaultInterface.fTexImage2D = glTexImage2D;
            gDefaultInterface.fTexParameteri = glTexParameteri;
            gDefaultInterface.fTexCoordPointer = glTexCoordPointer;
            gDefaultInterface.fTexEnvi = glTexEnvi;
            gDefaultInterface.fTexSubImage2D = glTexSubImage2D;
            gDefaultInterface.fViewport = glViewport;
            gDefaultInterface.fVertexPointer = glVertexPointer;

            GR_GL_GET_PROC(ActiveTexture);
            GR_GL_GET_PROC(AttachShader);
            GR_GL_GET_PROC(BindAttribLocation);
            GR_GL_GET_PROC(BindBuffer);
            GR_GL_GET_PROC(BindTexture);
            GR_GL_GET_PROC(BlendColor);
            GR_GL_GET_PROC(BufferData);
            GR_GL_GET_PROC(BufferSubData);
            GR_GL_GET_PROC(ClientActiveTexture);
            GR_GL_GET_PROC(CompileShader);
            GR_GL_GET_PROC(CompressedTexImage2D);
            GR_GL_GET_PROC(CreateProgram);
            GR_GL_GET_PROC(CreateShader);
            GR_GL_GET_PROC(DeleteBuffers);
            GR_GL_GET_PROC(DeleteProgram);
            GR_GL_GET_PROC(DeleteShader);
            GR_GL_GET_PROC(DisableVertexAttribArray);
            GR_GL_GET_PROC(DrawBuffers);
            GR_GL_GET_PROC(EnableVertexAttribArray);
            GR_GL_GET_PROC(GenBuffers);
            GR_GL_GET_PROC(GetBufferParameteriv);
            GR_GL_GET_PROC(GetProgramInfoLog);
            GR_GL_GET_PROC(GetProgramiv);
            GR_GL_GET_PROC(GetShaderInfoLog);
            GR_GL_GET_PROC(GetShaderiv);
            GR_GL_GET_PROC(GetUniformLocation);
            GR_GL_GET_PROC(LinkProgram);
            GR_GL_GET_PROC(ShaderSource);
            GR_GL_GET_PROC(StencilFuncSeparate);
            GR_GL_GET_PROC(StencilMaskSeparate);
            GR_GL_GET_PROC(StencilOpSeparate);
            GR_GL_GET_PROC(Uniform1f);
            GR_GL_GET_PROC(Uniform1i);
            GR_GL_GET_PROC(Uniform1fv);
            GR_GL_GET_PROC(Uniform1iv);
            GR_GL_GET_PROC(Uniform2f);
            GR_GL_GET_PROC(Uniform2i);
            GR_GL_GET_PROC(Uniform2fv);
            GR_GL_GET_PROC(Uniform2iv);
            GR_GL_GET_PROC(Uniform3f);
            GR_GL_GET_PROC(Uniform3i);
            GR_GL_GET_PROC(Uniform3fv);
            GR_GL_GET_PROC(Uniform3iv);
            GR_GL_GET_PROC(Uniform4f);
            GR_GL_GET_PROC(Uniform4i);
            GR_GL_GET_PROC(Uniform4fv);
            GR_GL_GET_PROC(Uniform4iv);
            GR_GL_GET_PROC(UniformMatrix2fv);
            GR_GL_GET_PROC(UniformMatrix3fv);
            GR_GL_GET_PROC(UniformMatrix4fv);
            GR_GL_GET_PROC(UseProgram);
            GR_GL_GET_PROC(VertexAttrib4fv);
            GR_GL_GET_PROC(VertexAttribPointer);
            GR_GL_GET_PROC(BindFragDataLocationIndexed);

            // First look for GL3.0 FBO or GL_ARB_framebuffer_object (same since
            // GL_ARB_framebuffer_object doesn't use ARB suffix.)
            if (major >= 3 || has_gl_extension_from_string("GL_ARB_framebuffer_object", extString)) {
                GR_GL_GET_PROC(GenFramebuffers);
                GR_GL_GET_PROC(GetFramebufferAttachmentParameteriv);
                GR_GL_GET_PROC(GetRenderbufferParameteriv);
                GR_GL_GET_PROC(BindFramebuffer);
                GR_GL_GET_PROC(FramebufferTexture2D);
                GR_GL_GET_PROC(CheckFramebufferStatus);
                GR_GL_GET_PROC(DeleteFramebuffers);
                GR_GL_GET_PROC(RenderbufferStorage);
                GR_GL_GET_PROC(GenRenderbuffers);
                GR_GL_GET_PROC(DeleteRenderbuffers);
                GR_GL_GET_PROC(FramebufferRenderbuffer);
                GR_GL_GET_PROC(BindRenderbuffer);
                GR_GL_GET_PROC(RenderbufferStorageMultisample);
                GR_GL_GET_PROC(BlitFramebuffer);
            } else if (has_gl_extension_from_string("GL_EXT_framebuffer_object", extString)) {
                GR_GL_GET_PROC_SUFFIX(GenFramebuffers, EXT);
                GR_GL_GET_PROC_SUFFIX(GetFramebufferAttachmentParameteriv, EXT);
                GR_GL_GET_PROC_SUFFIX(GetRenderbufferParameteriv, EXT);
                GR_GL_GET_PROC_SUFFIX(BindFramebuffer, EXT);
                GR_GL_GET_PROC_SUFFIX(FramebufferTexture2D, EXT);
                GR_GL_GET_PROC_SUFFIX(CheckFramebufferStatus, EXT);
                GR_GL_GET_PROC_SUFFIX(DeleteFramebuffers, EXT);
                GR_GL_GET_PROC_SUFFIX(RenderbufferStorage, EXT);
                GR_GL_GET_PROC_SUFFIX(GenRenderbuffers, EXT);
                GR_GL_GET_PROC_SUFFIX(DeleteRenderbuffers, EXT);
                GR_GL_GET_PROC_SUFFIX(FramebufferRenderbuffer, EXT);
                GR_GL_GET_PROC_SUFFIX(BindRenderbuffer, EXT);
                if (has_gl_extension_from_string("GL_EXT_framebuffer_multisample", extString)) {
                    GR_GL_GET_PROC_SUFFIX(RenderbufferStorageMultisample, EXT);
                }
                if (has_gl_extension_from_string("GL_EXT_framebuffer_blit", extString)) {
                    GR_GL_GET_PROC_SUFFIX(BlitFramebuffer, EXT);
                }
            } else {
                // we must have FBOs
                return;
            }
            GR_GL_GET_PROC(MapBuffer);
            GR_GL_GET_PROC(UnmapBuffer);

            gDefaultInterface.fBindingsExported = kDesktop_GrGLBinding;

            gDefaultInterfaceInit = true;
        }
    }
    if (gDefaultInterfaceInit) {
        GrGLSetGLInterface(&gDefaultInterface);
    }
}