EGLWLMockNavigation: add a texture loader

Add the class TextureLoader for loading textures in different formats.
TextureLoader can currently load textures in two formats: BMP and
byte array.

Also update CMakeLists.txt to include:
    include/TextureLoader.h
    src/TextureLoader.cpp

Signed-off-by: Michael Rodin <mrodin@de.adit-jv.com>

3 files changed, 180 insertions, 0 deletions

diff --git a/ivi-layermanagement-examples/EGLWLMockNavigation/CMakeLists.txt b/ivi-layermanagement-examples/EGLWLMockNavigation/CMakeLists.txt
index 91c9237..5b92848 100644
--- a/ivi-layermanagement-examples/EGLWLMockNavigation/CMakeLists.txt
+++ b/ivi-layermanagement-examples/EGLWLMockNavigation/CMakeLists.txt
@@ -2,6 +2,7 @@
 #
 # Copyright 2010-2014 BMW Car IT GmbH
 # Copyright (C) 2011 DENSO CORPORATION and Robert Bosch Car Multimedia Gmbh
+# Copyright (C) 2018 Advanced Driver Information Technology Joint Venture GmbH
 #
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -74,6 +75,7 @@ set (HEADER_FILES
     include/Street.h
     include/ShaderBase.h
     include/ShaderLighting.h
+    include/TextureLoader.h
 )
 
 set (SRC_FILES
@@ -88,6 +90,7 @@ set (SRC_FILES
     src/ShaderBase.cpp
     src/ShaderLighting.cpp
     src/main.cpp
+    src/TextureLoader.cpp
 )
 
 add_executable(${PROJECT_NAME}
diff --git a/ivi-layermanagement-examples/EGLWLMockNavigation/include/TextureLoader.h b/ivi-layermanagement-examples/EGLWLMockNavigation/include/TextureLoader.h
new file mode 100644
index 0000000..8a1dfdf
--- /dev/null
+++ b/ivi-layermanagement-examples/EGLWLMockNavigation/include/TextureLoader.h
@@ -0,0 +1,44 @@
+/***************************************************************************
+ *
+ * Copyright (C) 2018 Advanced Driver Information Technology Joint Venture GmbH
+ *
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ ****************************************************************************/
+#ifndef _TEXTURE_LOADER_H
+#define _TEXTURE_LOADER_H
+
+#include <string.h>
+
+#include <iostream>
+using std::cout;
+using std::endl;
+
+#include <GLES2/gl2.h>
+
+class TextureLoader
+{
+public:
+    TextureLoader();
+
+    bool loadBMP(const char * imagePath);
+    bool loadArray(void * data, unsigned int width, unsigned int height, unsigned int pixelSizeBits);
+    GLuint getId();
+
+private:
+    GLuint textureID;
+    bool loaded = false;
+};
+
+#endif
diff --git a/ivi-layermanagement-examples/EGLWLMockNavigation/src/TextureLoader.cpp b/ivi-layermanagement-examples/EGLWLMockNavigation/src/TextureLoader.cpp
new file mode 100644
index 0000000..30c170f
--- /dev/null
+++ b/ivi-layermanagement-examples/EGLWLMockNavigation/src/TextureLoader.cpp
@@ -0,0 +1,133 @@
+/***************************************************************************
+ *
+ * Copyright (C) 2018 Advanced Driver Information Technology Joint Venture GmbH
+ *
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ ****************************************************************************/
+#include "TextureLoader.h"
+
+TextureLoader::TextureLoader(){
+    ;
+}
+
+// source: http://www.opengl-tutorial.org/beginners-tutorials/tutorial-5-a-textured-cube/
+bool TextureLoader::loadBMP(const char * imagePath) {
+    // Data read from the header of the BMP file
+    const unsigned char headerSize = 54; // Each BMP file begins by a 54-bytes header
+    unsigned char header[headerSize];
+    GLsizei width, height;
+    uint16_t pixelSizeBits;
+    uint8_t pixelSizeBytes;
+    // imageSize == width*height*pixelSize, because each pixel consists of pixelSize bytes (red, green and blue)
+    unsigned int imageSize;
+    unsigned char * data;
+    FILE * file = fopen(imagePath,"rb");
+    if (!file) {
+        //cout << "Image file could not be opened: " << imagePath << endl;
+        return false;
+    }
+    if (fread(header, 1, headerSize, file) != headerSize) {
+        cout << "Not a correct BMP file (could not read the header): " << imagePath << endl;
+        fclose(file);
+        return false;
+    }
+    if (header[0]!='B' || header[1]!='M' ) {
+        cout << "Not a correct BMP file (wrong header format) :" << imagePath << endl;
+        fclose(file);
+        return false;
+    }
+    // Read fields from the BMP file header
+    imageSize  = *(int*)(header + 0x22);
+    width      = *(GLsizei*)(header + 0x12);
+    height     = *(GLsizei*)(header + 0x16);
+    pixelSizeBits  = *(uint16_t*)(header + 0x1C);
+    pixelSizeBytes = pixelSizeBits / 8;
+
+    if ((pixelSizeBits != 24) and (pixelSizeBits != 32)) {
+        cout << "unsupported pixel size of " << pixelSizeBits << " bits" << endl;
+        fclose(file);
+        return false;
+    }
+
+    // calculate the image size if there is no information in the header
+    if (imageSize==0) {
+        imageSize=width*height*pixelSizeBytes;
+    }
+
+    data = new unsigned char [imageSize];
+    fread(data,1,imageSize,file);
+    fclose(file);
+
+    if (pixelSizeBits == 32) {
+        // BMP files with an alpha channel use ABGR format for storing pixels
+        // OpenGLES does not have an ABGR format specifier
+        // therefore change pixel format from ABGR to RGBA
+        for (long long i = 0; i < width*height; i++) {
+            unsigned char a = data[i*pixelSizeBytes + 0];
+            unsigned char b = data[i*pixelSizeBytes + 1];
+            unsigned char g = data[i*pixelSizeBytes + 2];
+            unsigned char r = data[i*pixelSizeBytes + 3];
+            data[i*pixelSizeBytes]     = r;
+            data[i*pixelSizeBytes + 1] = g;
+            data[i*pixelSizeBytes + 2] = b;
+            data[i*pixelSizeBytes + 3] = a;
+        }
+    } else if (pixelSizeBits == 24) {
+        for (long long i = 0; i < width*height; i++) {
+            unsigned char b = data[i*pixelSizeBytes];
+            unsigned char g = data[i*pixelSizeBytes + 1];
+            unsigned char r = data[i*pixelSizeBytes + 2];
+            data[i*pixelSizeBytes]     = r;
+            data[i*pixelSizeBytes + 1] = g;
+            data[i*pixelSizeBytes + 2] = b;
+        }
+    }
+
+    bool loaded = loadArray(data, width, height, pixelSizeBits);
+    delete[] data;
+    return loaded;
+}
+
+// This function loads an array with image data
+bool TextureLoader::loadArray(void * data, unsigned int width, unsigned int height, unsigned int pixelSizeBits) {
+    if (loaded)
+        // don't load the thexture if a texture was already loaded for this object
+        return false;
+    else
+        loaded = true;
+    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+    glGenTextures(1, &textureID);
+    glBindTexture(GL_TEXTURE_2D, textureID);
+    if (pixelSizeBits == 32) {
+        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, data);
+        glEnable(GL_BLEND);
+        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+    } else if (pixelSizeBits == 24) {
+        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, data);
+        glEnable(GL_BLEND);
+        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+    }
+    glGenerateMipmap(GL_TEXTURE_2D);
+    // set texture parameters
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+    return loaded;
+}
+
+GLuint TextureLoader::getId() {
+    return textureID;
+}