a bit more opengl refactoring:

* added Access parameter to GlBuffer::mapHost
* added autoRelease parameter to all create methods
* fixed indentation in gl_core_3_1
* minor improvments for opengl sample

modules/core/include/opencv2/core/opengl_interop.hpp

@@ -71,6 +71,13 @@ public:
         PIXEL_UNPACK_BUFFER  = 0x88EC  //!< The buffer will be used for writing to OpenGL textures
     };
 
+    enum Access
+    {
+        READ_ONLY  = 0x88B8,
+        WRITE_ONLY = 0x88B9,
+        READ_WRITE = 0x88BA
+    };
+
     //! create empty buffer
     GlBuffer();
 
@@ -79,15 +86,15 @@ public:
     GlBuffer(Size asize, int atype, unsigned int abufId, bool autoRelease = false);
 
     //! create buffer
-    GlBuffer(int arows, int acols, int atype, Target target = ARRAY_BUFFER);
-    GlBuffer(Size asize, int atype, Target target = ARRAY_BUFFER);
+    GlBuffer(int arows, int acols, int atype, Target target = ARRAY_BUFFER, bool autoRelease = false);
+    GlBuffer(Size asize, int atype, Target target = ARRAY_BUFFER, bool autoRelease = false);
 
     //! copy from host/device memory
-    explicit GlBuffer(InputArray arr, Target target = ARRAY_BUFFER);
+    explicit GlBuffer(InputArray arr, Target target = ARRAY_BUFFER, bool autoRelease = false);
 
     //! create buffer
-    void create(int arows, int acols, int atype, Target target = ARRAY_BUFFER);
-    void create(Size asize, int atype, Target target = ARRAY_BUFFER) { create(asize.height, asize.width, atype, target); }
+    void create(int arows, int acols, int atype, Target target = ARRAY_BUFFER, bool autoRelease = false);
+    void create(Size asize, int atype, Target target = ARRAY_BUFFER, bool autoRelease = false) { create(asize.height, asize.width, atype, target, autoRelease); }
 
     //! release memory and delete buffer object
     void release();
@@ -96,7 +103,7 @@ public:
     void setAutoRelease(bool flag);
 
     //! copy from host/device memory
-    void copyFrom(InputArray arr, Target target = ARRAY_BUFFER);
+    void copyFrom(InputArray arr, Target target = ARRAY_BUFFER, bool autoRelease = false);
 
     //! copy to host/device memory
     void copyTo(OutputArray arr, Target target = ARRAY_BUFFER) const;
@@ -111,7 +118,7 @@ public:
     static void unbind(Target target);
 
     //! map to host memory
-    Mat mapHost();
+    Mat mapHost(Access access);
     void unmapHost();
 
     //! map to device memory
@@ -162,15 +169,15 @@ public:
     GlTexture2D(Size asize, Format aformat, unsigned int atexId, bool autoRelease = false);
 
     //! create texture
-    GlTexture2D(int arows, int acols, Format aformat);
-    GlTexture2D(Size asize, Format aformat);
+    GlTexture2D(int arows, int acols, Format aformat, bool autoRelease = false);
+    GlTexture2D(Size asize, Format aformat, bool autoRelease = false);
 
     //! copy from host/device memory
-    explicit GlTexture2D(InputArray arr);
+    explicit GlTexture2D(InputArray arr, bool autoRelease = false);
 
     //! create texture
-    void create(int arows, int acols, Format aformat);
-    void create(Size asize, Format aformat) { create(asize.height, asize.width, aformat); }
+    void create(int arows, int acols, Format aformat, bool autoRelease = false);
+    void create(Size asize, Format aformat, bool autoRelease = false) { create(asize.height, asize.width, aformat, autoRelease); }
 
     //! release memory and delete texture object
     void release();
@@ -179,7 +186,7 @@ public:
     void setAutoRelease(bool flag);
 
     //! copy from host/device memory
-    void copyFrom(InputArray arr);
+    void copyFrom(InputArray arr, bool autoRelease = false);
 
     //! copy to host/device memory
     void copyTo(OutputArray arr, int ddepth = CV_32F) const;

modules/gpu/test/test_opengl.cpp

@@ -351,14 +351,14 @@ TEST_P(GlBuffer, Clone)
     cv::destroyAllWindows();
 }
 
-TEST_P(GlBuffer, MapHost)
+TEST_P(GlBuffer, MapHostRead)
 {
     cv::namedWindow("test", cv::WINDOW_OPENGL);
 
     cv::Mat gold = randomMat(size, type);
     cv::GlBuffer buf(gold);
 
-    cv::Mat dst = buf.mapHost();
+    cv::Mat dst = buf.mapHost(cv::GlBuffer::READ_ONLY);
 
     EXPECT_MAT_NEAR(gold, dst, 0);
 
@@ -368,6 +368,27 @@ TEST_P(GlBuffer, MapHost)
     cv::destroyAllWindows();
 }
 
+TEST_P(GlBuffer, MapHostWrite)
+{
+    cv::namedWindow("test", cv::WINDOW_OPENGL);
+
+    cv::Mat gold = randomMat(size, type);
+    cv::GlBuffer buf(size, type);
+
+    cv::Mat dst = buf.mapHost(cv::GlBuffer::WRITE_ONLY);
+    gold.copyTo(dst);
+    buf.unmapHost();
+    dst.release();
+
+    cv::Mat bufData;
+    buf.copyTo(bufData);
+
+    EXPECT_MAT_NEAR(gold, bufData, 0);
+
+    buf.release();
+    cv::destroyAllWindows();
+}
+
 TEST_P(GlBuffer, MapDevice)
 {
     cv::namedWindow("test", cv::WINDOW_OPENGL);

samples/gpu/opengl.cpp

@@ -56,14 +56,18 @@ void CV_CDECL draw(void* userdata)
 
     glMatrixMode(GL_MODELVIEW);
     glLoadIdentity();
-    gluLookAt(0, 0, 4, 0, 0, 0, 0, 1, 0);
+    gluLookAt(0, 0, 3, 0, 0, 0, 0, 1, 0);
     glRotated(angle, 0, 1, 0);
 
     glEnable(GL_TEXTURE_2D);
     data->tex.bind();
 
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    glTexEnvi(GL_TEXTURE_2D, GL_TEXTURE_ENV_MODE, GL_REPLACE);
+
     glDisable(GL_CULL_FACE);
-    glHint(GL_POLYGON_SMOOTH_HINT, GL_NICEST);
 
     render(data->arr, data->indices, RenderMode::TRIANGLES);
 
@@ -101,13 +105,8 @@ int main(int argc, char* argv[])
 
     data.arr.setVertexArray(vertex);
     data.arr.setTexCoordArray(texCoords);
-    data.arr.setAutoRelease(false);
-
     data.indices.copyFrom(indices);
-    data.indices.setAutoRelease(false);
-
     data.tex.copyFrom(img);
-    data.tex.setAutoRelease(false);
 
     setOpenGlDrawCallback("OpenGL", draw, &data);