Remove the default pixel format, fix rendering of grayscale PNGs (#2573)

* Add AXMOL_AUTOTEST_CAPTURE_DIR for cpp-tests.

In auto test mode, cpp-tests will save a capture of the scene in the
directory whose path is given by environment variable
AXMOL_AUTOTEST_CAPTURE_DIR, if such a path is provided.

* Check the value of AXMOL_START_AUTOTEST, ignore it if zero.

* Remove the default pixel format from Texture2D, use the source format.

* Handle gray+alpha PNG images as gray+alpha sprites.

Author: j-jorge

core/2d/AnchoredSprite.cpp

@@ -71,7 +71,7 @@ AnchoredSprite* AnchoredSprite::createWithTexture(Texture2D* texture, const Rect
 
 AnchoredSprite* AnchoredSprite::create(std::string_view filename)
 {
-    return AnchoredSprite::create(filename, Texture2D::getDefaultAlphaPixelFormat());
+    return AnchoredSprite::create(filename, PixelFormat::NONE);
 }
 
 AnchoredSprite* AnchoredSprite::create(std::string_view filename, PixelFormat format)

core/2d/Sprite.cpp

@@ -75,7 +75,7 @@ Sprite* Sprite::createWithTexture(Texture2D* texture, const Rect& rect, bool rot
 
 Sprite* Sprite::create(std::string_view filename)
 {
-    return Sprite::create(filename, Texture2D::getDefaultAlphaPixelFormat());
+    return Sprite::create(filename, PixelFormat::NONE);
 }
 
 Sprite* Sprite::create(std::string_view filename, PixelFormat format)
@@ -187,7 +187,7 @@ bool Sprite::initWithTexture(Texture2D* texture, const Rect& rect)
 
 bool Sprite::initWithFile(std::string_view filename)
 {
-    return initWithFile(filename, Texture2D::getDefaultAlphaPixelFormat());
+    return initWithFile(filename, PixelFormat::NONE);
 }
 
 bool Sprite::initWithFile(std::string_view filename, PixelFormat format)
@@ -434,7 +434,25 @@ void Sprite::setTexture(Texture2D* texture)
     }
 
     if (needsUpdatePS)
-        setProgramState(backend::ProgramType::POSITION_TEXTURE_COLOR);
+    {
+        const PixelFormat pixelFormat = _texture->getPixelFormat();
+
+        switch(pixelFormat)
+          {
+          case PixelFormat::R8:
+            setProgramState(backend::ProgramType::POSITION_TEXTURE_GRAY);
+            break;
+          case PixelFormat::RG8:
+            setProgramState(backend::ProgramType::POSITION_TEXTURE_GRAY_ALPHA);
+            break;
+          case PixelFormat::RGBA8:
+            setProgramState(backend::ProgramType::POSITION_TEXTURE_COLOR);
+            break;
+          default:
+            AXLOGW("Warning: Sprite::setTexture() unhandled pixel format {}", (int)pixelFormat);
+            setProgramState(backend::ProgramType::POSITION_TEXTURE_COLOR);
+          }
+    }
     else
         updateProgramStateTexture(_texture);
 }

core/base/Director.cpp

@@ -229,15 +229,6 @@ void Director::setDefaultValues()
     else
         AXASSERT(false, "Invalid projection value");
 
-    // Default pixel format for PNG images with alpha
-    std::string pixel_format = conf->getValue("axmol.texture.pixel_format_for_png", Value("rgba8888")).asString();
-    if (pixel_format == "rgba8888")
-        Texture2D::setDefaultAlphaPixelFormat(backend::PixelFormat::RGBA8);
-    else if (pixel_format == "rgba4444")
-        Texture2D::setDefaultAlphaPixelFormat(backend::PixelFormat::RGBA4);
-    else if (pixel_format == "rgba5551")
-        Texture2D::setDefaultAlphaPixelFormat(backend::PixelFormat::RGB5A1);
-
     /* !!!Notes
     ** All compressed image should do PMA at texture convert tools(such as astcenc-2.2+ with -pp-premultiply)
     ** or GPU fragment shader
@@ -1318,7 +1309,7 @@ void Director::createStatsLabel()
         return;
     }
 
-    texture = _textureCache->addImage(image, "/ax_fps_images", PixelFormat::RGBA4);
+    texture = _textureCache->addImage(image, "/ax_fps_images");
     AX_SAFE_RELEASE(image);
 
     /*

core/platform/Image.cpp

@@ -1314,7 +1314,8 @@ bool Image::initWithPngData(uint8_t* data, ssize_t dataLen)
         png_read_end(png_ptr, nullptr);
 
         // premultiplied alpha for RGBA8888
-        if ((color_type == PNG_COLOR_TYPE_RGB_ALPHA) || (color_type == PNG_COLOR_TYPE_GRAY_ALPHA))
+        if ((color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+            || (color_type == PNG_COLOR_TYPE_GRAY_ALPHA))
         {
             if (PNG_PREMULTIPLIED_ALPHA_ENABLED)
             {
@@ -2635,7 +2636,7 @@ void Image::premultiplyAlpha()
         for (int i = 0; i < _width * _height; i++)
         {
             uint8_t* p   = _data + i * 2;
-            twoBytes[i] = ((p[0] * p[1] + 1) >> 8) | (p[1] << 8);
+            twoBytes[i] = ((p[0] * (p[1] + 1)) >> 8) | (p[1] << 8);
         }
     }
 

core/renderer/Shaders.cpp

@@ -39,6 +39,8 @@ AX_DLL const std::string_view positionTexture_frag                 = "positionTe
 AX_DLL const std::string_view positionTextureColor_vert            = "positionTextureColor_vs"sv;
 AX_DLL const std::string_view positionTextureColor_frag            = "positionTextureColor_fs"sv;
 AX_DLL const std::string_view positionTextureColorAlphaTest_frag   = "positionTextureColorAlphaTest_fs"sv;
+AX_DLL const std::string_view positionTextureGray_frag             = "positionTextureGray_fs"sv;
+AX_DLL const std::string_view positionTextureGrayAlpha_frag        = "positionTextureGrayAlpha_fs"sv;
 AX_DLL const std::string_view label_normal_frag                    = "label_normal_fs"sv;
 AX_DLL const std::string_view label_outline_frag                   = "label_outline_fs"sv;
 AX_DLL const std::string_view label_distanceNormal_frag            = "label_distanceNormal_fs"sv;

core/renderer/Shaders.h

@@ -47,6 +47,8 @@ extern AX_DLL const std::string_view positionTexture_frag;
 extern AX_DLL const std::string_view positionTextureColor_vert;
 extern AX_DLL const std::string_view positionTextureColor_frag;
 extern AX_DLL const std::string_view positionTextureColorAlphaTest_frag;
+extern AX_DLL const std::string_view positionTextureGray_frag;
+extern AX_DLL const std::string_view positionTextureGrayAlpha_frag;
 extern AX_DLL const std::string_view label_normal_frag;
 extern AX_DLL const std::string_view label_outline_frag;
 extern AX_DLL const std::string_view label_distanceNormal_frag;

core/renderer/Texture2D.cpp

@@ -56,12 +56,6 @@ THE SOFTWARE.
 namespace ax
 {
 
-// CLASS IMPLEMENTATIONS:
-
-// If the image has alpha, you can create RGBA8 (32-bit) or RGBA4 (16-bit) or RGB5A1 (16-bit)
-// Default is: RGBA8888 (32-bit textures)
-static backend::PixelFormat g_defaultAlphaPixelFormat = backend::PixelFormat::RGBA8;
-
 Texture2D::Texture2D()
     : _pixelFormat(backend::PixelFormat::NONE)
     , _pixelsWide(0)
@@ -188,6 +182,11 @@ bool Texture2D::initWithMipmaps(MipmapInfo* mipmaps,
     return true;
 }
 
+bool Texture2D::updateWithImage(Image* image, int index)
+{
+    return updateWithImage(image, image->getPixelFormat(), index);
+}
+
 bool Texture2D::updateWithImage(Image* image, backend::PixelFormat format, int index)
 {
     if (image == nullptr)
@@ -237,34 +236,24 @@ bool Texture2D::updateWithImage(Image* image, backend::PixelFormat format, int i
     default:
         break;
     }
-#elif !AX_GLES_PROFILE
-    // Non-GLES doesn't support follow render formats, needs convert PixelFormat::RGBA8
-    // Note: axmol-1.1 deprecated A8, L8, LA8 as renderFormat, preferred R8, RG8
-    switch (renderFormat)
-    {
-    case PixelFormat::R8:
-    case PixelFormat::RG8:
-        // Note: conversion to RGBA8 will happends
-        renderFormat = PixelFormat::RGBA8;
-    }
 #endif
 
     if (image->getNumberOfMipmaps() > 1)
     {
-        if (renderFormat != image->getPixelFormat())
+        if (renderFormat != imagePixelFormat)
         {
             AXLOGW("WARNING: This image has more than 1 mipmaps and we will not convert the data format");
         }
 
         // pixel format of data is not converted, renderFormat can be different from pixelFormat
         // it will be done later
-        updateWithMipmaps(image->getMipmaps(), image->getNumberOfMipmaps(), image->getPixelFormat(), renderFormat, imageHeight, imageWidth, image->hasPremultipliedAlpha(), index);
+        updateWithMipmaps(image->getMipmaps(), image->getNumberOfMipmaps(), imagePixelFormat, renderFormat, imageHeight, imageWidth, image->hasPremultipliedAlpha(), index);
     }
     else if (image->isCompressed())
     {  // !Only hardware support texture will be compression PixelFormat, otherwise, will convert to RGBA8 duraing image
        // load
         renderFormat = imagePixelFormat;
-        updateWithData(tempData, tempDataLen, image->getPixelFormat(), image->getPixelFormat(), imageWidth, imageHeight, image->hasPremultipliedAlpha(), index);
+        updateWithData(tempData, tempDataLen, imagePixelFormat, image->getPixelFormat(), imageWidth, imageHeight, image->hasPremultipliedAlpha(), index);
     }
     else
     {
@@ -448,7 +437,13 @@ bool Texture2D::updateWithSubData(void* data, int offsetX, int offsetY, int widt
 // implementation Texture2D (Image)
 bool Texture2D::initWithImage(Image* image)
 {
-    return initWithImage(image, g_defaultAlphaPixelFormat);
+    if (image == nullptr)
+    {
+        AXLOGW("Texture2D. Can't create Texture. UIImage is nil");
+        return false;
+    }
+
+    return initWithImage(image, image->getPixelFormat());
 }
 
 bool Texture2D::initWithImage(Image* image, backend::PixelFormat format)
@@ -532,10 +527,6 @@ bool Texture2D::initWithString(std::string_view text, const FontDefinition& text
     AXASSERT(textDefinition._stroke._strokeEnabled == false, "Currently stroke only supported on iOS and Android!");
 #endif
 
-    PixelFormat pixelFormat    = g_defaultAlphaPixelFormat;
-    unsigned char* outTempData = nullptr;
-    size_t outTempDataLen      = 0;
-
     int imageWidth;
     int imageHeight;
     auto textDef            = textDefinition;
@@ -560,16 +551,10 @@ bool Texture2D::initWithString(std::string_view text, const FontDefinition& text
     }
 
     Vec2 imageSize = Vec2((float)imageWidth, (float)imageHeight);
-    pixelFormat =
-        backend::PixelFormatUtils::convertDataToFormat(outData.getBytes(), imageWidth * imageHeight * 4,
-                                                       PixelFormat::RGBA8, pixelFormat, &outTempData, &outTempDataLen);
+    const PixelFormat pixelFormat = PixelFormat::RGBA8;
 
-    ret = initWithData(outTempData, outTempDataLen, pixelFormat, imageWidth, imageHeight);
+    ret = initWithData(outData.getBytes(), imageWidth * imageHeight * 4, pixelFormat, imageWidth, imageHeight);
 
-    if (outTempData != nullptr && outTempData != outData.getBytes())
-    {
-        free(outTempData);
-    }
     setPremultipliedAlpha(hasPremultipliedAlpha);
 
     return ret;
@@ -647,21 +632,6 @@ const char* Texture2D::getStringForFormat() const
     return backend::PixelFormatUtils::getFormatDescriptor(_pixelFormat).name;
 }
 
-//
-// Texture options for images that contains alpha
-//
-// implementation Texture2D (PixelFormat)
-
-void Texture2D::setDefaultAlphaPixelFormat(backend::PixelFormat format)
-{
-    g_defaultAlphaPixelFormat = format;
-}
-
-backend::PixelFormat Texture2D::getDefaultAlphaPixelFormat()
-{
-    return g_defaultAlphaPixelFormat;
-}
-
 unsigned int Texture2D::getBitsPerPixelForFormat(backend::PixelFormat format) const
 {
     return backend::PixelFormatUtils::getFormatDescriptor(format).bpp;

core/renderer/Texture2D.h

@@ -91,36 +91,6 @@ class AX_DLL Texture2D : public Object
      */
     using TexParams = backend::SamplerDescriptor;
 
-public:
-    /** sets the default pixel format for UIImagescontains alpha channel.
-
-     @param format
-     If the UIImage contains alpha channel, then the options are:
-     - generate 32-bit textures: backend::PixelFormat::RGBA8 (default one)
-     - generate 24-bit textures: backend::PixelFormat::RGB8
-     - generate 16-bit textures: backend::PixelFormat::RGBA4
-     - generate 16-bit textures: backend::PixelFormat::RGB5A1
-     - generate 16-bit textures: backend::PixelFormat::RGB565
-     - generate 8-bit textures: backend::PixelFormat::R8 (only use it if you use just 1 color)
-     - generate 16-bit textures: backend::PixelFormat::RG8 (only use it if you use just 2 color)
-
-     How does it work ?
-     - If the image is an RGBA (with Alpha) then the default pixel format will be used (it can be a 8-bit, 16-bit or
-     32-bit texture)
-     - If the image is an RGB (without Alpha) then: If the default pixel format is RGBA8888 then a RGBA8888 (32-bit)
-     will be used. Otherwise a RGB565 (16-bit texture) will be used.
-
-     This parameter is not valid for PVR / PVR.CCZ images.
-
-     @since v0.8
-     */
-    static void setDefaultAlphaPixelFormat(backend::PixelFormat format);
-
-    /** Returns the alpha pixel format.
-     @since v0.8
-     */
-    static backend::PixelFormat getDefaultAlphaPixelFormat();
-
 public:
     /**
      */
@@ -197,6 +167,7 @@ class AX_DLL Texture2D : public Object
     @param width Specifies the width of the texture subimage.
     @param height Specifies the height of the texture subimage.
     */
+    bool updateWithImage(Image* image, int index = 0);
     bool updateWithImage(Image* image, backend::PixelFormat format, int index = 0);
     bool updateWithData(const void* data,
                         ssize_t dataLen,
@@ -240,21 +211,19 @@ class AX_DLL Texture2D : public Object
     /**
     Initializes a texture from a UIImage object.
 
-    We will use the format you specified with setDefaultAlphaPixelFormat to convert the image for texture.
+    We will use the pixel format of the image.
     NOTE: It will not convert the pvr image file.
     @param image An UIImage object.
     */
     bool initWithImage(Image* image);
 
     /**
-    Initializes a texture from a UIImage object.
+    Initializes a texture from an Image object and convert it to the given
+    format if necessary.
 
-    We will use the format you passed to the function to convert the image format to the texture format.
-    If you pass PixelFormat::NONE, we will auto detect the image render type and use that type for texture to render.
-    @param image An UIImage object.
-    @param format Texture pixel formats.
-    **/
-    bool initWithImage(Image* image, backend::PixelFormat format);
+    NOTE: It will not convert the pvr image file.
+    */
+    bool initWithImage(Image* image, PixelFormat format);
 
     /** Initializes a texture from a string with dimensions, alignment, font name and font size.
 

core/renderer/TextureCache.cpp

@@ -87,7 +87,7 @@ struct TextureCache::AsyncStruct
         : filename(fn)
         , callback(f)
         , callbackKey(key)
-        , pixelFormat(Texture2D::getDefaultAlphaPixelFormat())
+        , pixelFormat(PixelFormat::NONE)
         , loadSuccess(false)
     {}
 
@@ -433,7 +433,7 @@ Texture2D* TextureCache::getDummyTexture()
 
 Texture2D* TextureCache::addImage(std::string_view path)
 {
-    return addImage(path, Texture2D::getDefaultAlphaPixelFormat());
+    return addImage(path, PixelFormat::NONE);
 }
 
 Texture2D* TextureCache::addImage(std::string_view path, PixelFormat format)
@@ -516,7 +516,7 @@ void TextureCache::parseNinePatchImage(ax::Image* image, ax::Texture2D* texture,
 
 Texture2D* TextureCache::addImage(Image* image, std::string_view key)
 {
-    return addImage(image, key, Texture2D::getDefaultAlphaPixelFormat());
+    return addImage(image, key, PixelFormat::NONE);
 }
 
 Texture2D* TextureCache::addImage(Image* image, std::string_view key, PixelFormat format)

core/renderer/TextureCache.h

@@ -112,8 +112,6 @@ class AX_DLL TextureCache : public Object
      @param filepath The file path.
      @param callback A callback function would be invoked after the image is loaded.
      @since v0.8
-
-     @remark Please don't invoke Texture2D::setDefaultAlphaPixelFormat in main GL thread before invoke this API.
     */
     virtual void addImageAsync(std::string_view filepath, const std::function<void(Texture2D*)>& callback);