Moved some backend-agnostic code out of the OpenGL backend of love.graphics.

--HG--
branch : minor

src/modules/graphics/Canvas.cpp

@@ -89,6 +89,53 @@ int Canvas::getRequestedMSAA() const
 	return settings.msaa;
 }
 
+love::image::ImageData *Canvas::newImageData(love::image::Image *module, int slice, int mipmap, const Rect &r)
+{
+	if (!isReadable())
+		throw love::Exception("Canvas:newImageData cannot be called on non-readable Canvases.");
+
+	if (isPixelFormatDepthStencil(getPixelFormat()))
+		throw love::Exception("Canvas:newImageData cannot be called on Canvases with depth/stencil pixel formats.");
+
+	if (r.x < 0 || r.y < 0 || r.w <= 0 || r.h <= 0 || (r.x + r.w) > getPixelWidth(mipmap) || (r.y + r.h) > getPixelHeight(mipmap))
+		throw love::Exception("Invalid rectangle dimensions.");
+
+	if (slice < 0 || (texType == TEXTURE_VOLUME && slice >= getDepth(mipmap))
+		|| (texType == TEXTURE_2D_ARRAY && slice >= layers)
+		|| (texType == TEXTURE_CUBE && slice >= 6))
+	{
+		throw love::Exception("Invalid slice index.");
+	}
+
+	Graphics *gfx = Module::getInstance<Graphics>(Module::M_GRAPHICS);
+	if (gfx != nullptr && gfx->isCanvasActive(this))
+		throw love::Exception("Canvas:newImageData cannot be called while that Canvas is currently active.");
+
+	PixelFormat dataformat;
+	switch (getPixelFormat())
+	{
+		case PIXELFORMAT_RGB10A2: // FIXME: Conversions aren't supported in GLES
+			dataformat = PIXELFORMAT_RGBA16;
+			break;
+		case PIXELFORMAT_R16F:
+		case PIXELFORMAT_RG16F:
+		case PIXELFORMAT_RGBA16F:
+		case PIXELFORMAT_RG11B10F: // FIXME: Conversions aren't supported in GLES
+			dataformat = PIXELFORMAT_RGBA16F;
+			break;
+		case PIXELFORMAT_R32F:
+		case PIXELFORMAT_RG32F:
+		case PIXELFORMAT_RGBA32F:
+			dataformat = PIXELFORMAT_RGBA32F;
+			break;
+		default:
+			dataformat = PIXELFORMAT_RGBA8;
+			break;
+	}
+
+	return module->newImageData(r.w, r.h, dataformat);
+}
+
 void Canvas::draw(Graphics *gfx, Quad *q, const Matrix4 &t)
 {
 	if (gfx->isCanvasActive(this))

src/modules/graphics/Canvas.h

@@ -66,7 +66,7 @@ public:
 	MipmapMode getMipmapMode() const;
 	int getRequestedMSAA() const;
 
-	virtual love::image::ImageData *newImageData(love::image::Image *module, int slice, int mipmap, const Rect &rect) = 0;
+	virtual love::image::ImageData *newImageData(love::image::Image *module, int slice, int mipmap, const Rect &rect);
 	virtual void generateMipmaps() = 0;
 
 	virtual int getMSAA() const = 0;

src/modules/graphics/opengl/Canvas.cpp

@@ -454,49 +454,8 @@ ptrdiff_t Canvas::getHandle() const
 
 love::image::ImageData *Canvas::newImageData(love::image::Image *module, int slice, int mipmap, const Rect &r)
 {
-	if (!isReadable())
-		throw love::Exception("Canvas:newImageData cannot be called on non-readable Canvases.");
-
-	if (isPixelFormatDepthStencil(getPixelFormat()))
-		throw love::Exception("Canvas:newImageData cannot be called on Canvases with depth/stencil pixel formats.");
-
-	if (r.x < 0 || r.y < 0 || r.w <= 0 || r.h <= 0 || (r.x + r.w) > getPixelWidth(mipmap) || (r.y + r.h) > getPixelHeight(mipmap))
-		throw love::Exception("Invalid rectangle dimensions.");
-
-	if (slice < 0 || (texType == TEXTURE_VOLUME && slice >= getDepth(mipmap))
-		|| (texType == TEXTURE_2D_ARRAY && slice >= layers)
-		|| (texType == TEXTURE_CUBE && slice >= 6))
-	{
-		throw love::Exception("Invalid slice index.");
-	}
-
-	Graphics *gfx = Module::getInstance<Graphics>(Module::M_GRAPHICS);
-	if (gfx != nullptr && gfx->isCanvasActive(this))
-		throw love::Exception("Canvas:newImageData cannot be called while that Canvas is currently active.");
-
-	PixelFormat dataformat;
-	switch (getPixelFormat())
-	{
-	case PIXELFORMAT_RGB10A2: // FIXME: Conversions aren't supported in GLES
-		dataformat = PIXELFORMAT_RGBA16;
-		break;
-	case PIXELFORMAT_R16F:
-	case PIXELFORMAT_RG16F:
-	case PIXELFORMAT_RGBA16F:
-	case PIXELFORMAT_RG11B10F: // FIXME: Conversions aren't supported in GLES
-		dataformat = PIXELFORMAT_RGBA16F;
-		break;
-	case PIXELFORMAT_R32F:
-	case PIXELFORMAT_RG32F:
-	case PIXELFORMAT_RGBA32F:
-		dataformat = PIXELFORMAT_RGBA32F;
-		break;
-	default:
-		dataformat = PIXELFORMAT_RGBA8;
-		break;
-	}
-
-	love::image::ImageData *imagedata = module->newImageData(r.w, r.h, dataformat);
+	love::image::ImageData *imagedata = love::graphics::Canvas::newImageData(module, slice, mipmap, r);
+	PixelFormat dataformat = imagedata->getFormat();
 
 	bool isSRGB = false;
 	OpenGL::TextureFormat fmt = gl.convertPixelFormat(dataformat, false, isSRGB);