gfx_opengl_shaders.h

/* 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 GRIM_GFX_OPENGL_SHADERS_H
#define GRIM_GFX_OPENGL_SHADERS_H

#include "engines/grim/actor.h"
#include "engines/grim/gfx_base.h"

#include "graphics/opengl/shader.h"

#include "common/stack.h"
#include "common/rect.h"

namespace Grim {

class GfxOpenGLS : public GfxBase {
public:
    GfxOpenGLS();
    virtual ~GfxOpenGLS();

    void setupScreen(int screenW, int screenH) override;

    bool isHardwareAccelerated() override { return true; };
    bool supportsShaders() override { return true; }
    void setupCameraFrustum(float fov, float nclip, float fclip) override;
    void positionCamera(const Math::Vector3d &pos, const Math::Vector3d &interest, float roll) override;
    void positionCamera(const Math::Vector3d &pos, const Math::Matrix4 &rot) override;

    Math::Matrix4 getModelView() override;
    Math::Matrix4 getProjection() override;

    void clearScreen() override;
    void clearDepthBuffer() override;

    void flipBuffer(bool opportunistic = false) override;

    void getScreenBoundingBox(const Mesh *mesh, int *x1, int *y1, int *x2, int *y2) override;
    void getScreenBoundingBox(const EMIModel *model, int *x1, int *y1, int *x2, int *y2) override;
    void getActorScreenBBox(const Actor *actor, Common::Point &p1, Common::Point &p2) override;
    void startActorDraw(const Actor *actor) override;

    void finishActorDraw() override;
    void setShadow(Shadow *shadow) override;
    void drawShadowPlanes() override;
    void setShadowMode() override;
    void clearShadowMode() override;
    bool isShadowModeActive() override;
    void setShadowColor(byte r, byte g, byte b) override;
    void getShadowColor(byte *r, byte *g, byte *b) override;
    void destroyShadow(Shadow *shadow) override;

    void set3DMode() override;

    void translateViewpointStart() override;
    void translateViewpoint(const Math::Vector3d &vec) override;
    void rotateViewpoint(const Math::Angle &angle, const Math::Vector3d &axis) override;
    void rotateViewpoint(const Math::Matrix4 &rot) override;
    void translateViewpointFinish() override;

    void drawEMIModelFace(const EMIModel* model, const EMIMeshFace* face) override;
    void drawModelFace(const Mesh *mesh, const MeshFace *face) override;
    void drawSprite(const Sprite *sprite) override;
    void drawMesh(const Mesh *mesh) override;
    void drawDimPlane() override;

    void enableLights() override;
    void disableLights() override;
    void setupLight(Light *light, int lightId) override;
    void turnOffLight(int lightId) override;

    void createTexture(Texture *texture, const uint8 *data, const CMap *cmap, bool clamp) override;
    void selectTexture(const Texture *texture) override;
    void destroyTexture(Texture *texture) override;

    void createBitmap(BitmapData *bitmap) override;

    void drawBitmap(const Bitmap *bitmap, int x, int y, uint32 layer = 0) override;

    void destroyBitmap(BitmapData *bitmap) override;

    void createFont(Font *font) override;
    void destroyFont(Font *font) override;

    void createTextObject(TextObject *text) override;
    void drawTextObject(const TextObject *text) override;
    void destroyTextObject(TextObject *text) override;

    Bitmap *getScreenshot(int w, int h, bool useStored) override;
    void storeDisplay() override;
    void copyStoredToDisplay() override;

    void dimScreen() override;
    void dimRegion(int x, int y, int w, int h, float level) override;

    void irisAroundRegion(int x1, int y1, int x2, int y2) override;

    void drawEmergString(int x, int y, const char *text, const Color &fgColor) override;
    void loadEmergFont() override;

    void drawRectangle(const PrimitiveObject *primitive) override;
    void drawLine(const PrimitiveObject *primitive) override;
    void drawPolygon(const PrimitiveObject *primitive) override;

    const Graphics::PixelFormat getMovieFormat() const override;

    void prepareMovieFrame(Graphics::Surface* frame) override;
    void drawMovieFrame(int offsetX, int offsetY) override;

    void releaseMovieFrame() override;

    const char *getVideoDeviceName() override;

    void renderBitmaps(bool render) override;
    void renderZBitmaps(bool render) override;

    void createMesh(Mesh *mesh) override;
    void destroyMesh(const Mesh *mesh) override;
    void createEMIModel(EMIModel *model) override;
    void updateEMIModel(const EMIModel* model) override;
    void destroyEMIModel(EMIModel *model) override;

    void setBlendMode(bool additive) override;

protected:
    void setupShaders();
    GLuint compileShader(const char *vertex, const char *fragment);
    GLuint compileShader(const char *shader) { return compileShader(shader, shader); }
    void createSpecialtyTextureFromScreen(uint id, uint8 *data, int x, int y, int width, int height) override;

private:
    const Actor *_currentActor;
    float _alpha;
    int _maxLights;
    GLuint _emergTexture;
    OpenGL::Shader* _emergProgram;

    OpenGL::Shader* _backgroundProgram;
    OpenGL::Shader* _actorProgram;
    OpenGL::Shader* _actorLightsProgram;
    OpenGL::Shader* _spriteProgram;
    OpenGL::Shader* _dimProgram;
    OpenGL::Shader* _dimPlaneProgram;
    OpenGL::Shader* _dimRegionProgram;
    OpenGL::Shader* _smushProgram;
    GLuint _smushVBO, _quadEBO;
    OpenGL::Shader* _textProgram;
    OpenGL::Shader* _primitiveProgram;
    OpenGL::Shader* _irisProgram;
    OpenGL::Shader* _shadowPlaneProgram;

    int _smushWidth;
    int _smushHeight;
    GLuint _smushTexId;
    void setupTexturedQuad();
    void setupQuadEBO();

    void setupZBuffer();
    void drawDepthBitmap(int bitmapId, int x, int y, int w, int h, char *data);

    float _fov;
    float _nclip;
    float _fclip;
    Math::Matrix4 _projMatrix;
    Math::Matrix4 _viewMatrix;
    Math::Matrix4 _mvpMatrix;
    Math::Matrix4 _overworldProjMatrix;

    void setupTexturedCenteredQuad();

    GLuint _spriteVBO;

    Common::Stack<Math::Matrix4> _matrixStack;
    Texture *_selectedTexture;

    GLuint _zBufTex;
    Math::Vector2d _zBufTexCrop;

    struct GLSLight {
        Math::Vector4d _position;
        Math::Vector4d _direction;
        Math::Vector4d _color;
        Math::Vector4d _params;
    };

    GLSLight *_lights;
    bool _hasAmbientLight;
    bool _lightsEnabled;

    void setupPrimitives();
    GLuint nextPrimitive();
    GLuint _primitiveVBOs[32];
    uint32 _currentPrimitive;
    void drawGenericPrimitive(const float *vertices, uint32 numVertices, const PrimitiveObject *primitive);
    GLuint _irisVBO;
    GLuint _dimVBO;
    GLuint _dimRegionVBO;
    GLuint _blastVBO;
    GLuint _storedDisplay;
};

}

#endif