2 files changed, 52 insertions, 16 deletions

diff --git a/backends/graphics/opengl/gltexture.cpp b/backends/graphics/opengl/gltexture.cpp
index ce69dc4aab..ca674563df 100644
--- a/backends/graphics/opengl/gltexture.cpp
+++ b/backends/graphics/opengl/gltexture.cpp
@@ -108,9 +108,18 @@ void GLTexture::allocBuffer(GLuint w, GLuint h) {
 	_realWidth = w;
 	_realHeight = h;
 
-	if (w <= _textureWidth && h <= _textureHeight && !_refresh)
-		// Already allocated a sufficiently large buffer
-		return;
+	if (!_refresh) {
+		if (npot_supported && _filter == GL_LINEAR) {
+			// Check if we already allocated a correctly-sized buffer
+			// This is so we don't need to duplicate the last row/column
+			if (w == _textureWidth && h == _textureHeight)
+				return;
+		} else {
+			// Check if we already have a large enough buffer
+			if (w <= _textureWidth && h <= _textureHeight)
+				return;
+		}
+	}
 
 	if (npot_supported) {
 		_textureWidth = w;
@@ -151,12 +160,37 @@ void GLTexture::updateBuffer(const void *buf, int pitch, GLuint x, GLuint y, GLu
 	} else {
 		// Update the texture row by row
 		const byte *src = (const byte *)buf;
+		GLuint curY = y;
+		GLuint height = h;
 		do {
-			glTexSubImage2D(GL_TEXTURE_2D, 0, x, y,
+			glTexSubImage2D(GL_TEXTURE_2D, 0, x, curY,
 			                w, 1, _glFormat, _glType, src); CHECK_GL_ERROR();
-			++y;
+			curY++;
 			src += pitch;
-		} while (--h);
+		} while (--height);
+	}
+
+	// If we're in linear filter mode, repeat the last row/column if the real dimensions
+	// doesn't match the texture dimensions.
+	if (_filter == GL_LINEAR) {
+		if (_realWidth != _textureWidth && x + w == _realWidth) {
+			const byte *src = (const byte *)buf + (w - 1) * _bytesPerPixel;
+			GLuint curY = y;
+			GLuint height = h;
+
+			do {
+				glTexSubImage2D(GL_TEXTURE_2D, 0, x + w,
+						curY, 1, 1, _glFormat, _glType, src); CHECK_GL_ERROR();
+
+				curY++;
+				src += pitch;
+			} while (--height);
+		}
+
+		if (_realHeight != _textureHeight && y + h == _realHeight) {
+			glTexSubImage2D(GL_TEXTURE_2D, 0, x, y + h,
+					w, 1, _glFormat, _glType, (const byte *)buf + pitch * (h - 1)); CHECK_GL_ERROR();
+		}
 	}
 }
 
@@ -177,10 +211,10 @@ void GLTexture::drawTexture(GLshort x, GLshort y, GLshort w, GLshort h) {
 
 	// Calculate the screen rect where the texture will be drawn
 	const GLshort vertices[] = {
-		x,      y,
-		x + w,  y,
-		x,      y + h,
-		x + w,  y + h,
+		x,                y,
+		(GLshort)(x + w), y,
+		x,                (GLshort)(y + h),
+		(GLshort)(x + w), (GLshort)(y + h),
 	};
 	glVertexPointer(2, GL_SHORT, 0, vertices); CHECK_GL_ERROR();
 
diff --git a/backends/graphics/opengl/opengl-graphics.cpp b/backends/graphics/opengl/opengl-graphics.cpp
index dce902d894..48e2663d44 100644
--- a/backends/graphics/opengl/opengl-graphics.cpp
+++ b/backends/graphics/opengl/opengl-graphics.cpp
@@ -902,7 +902,7 @@ void OpenGLGraphicsManager::getGLPixelFormat(Graphics::PixelFormat pixelFormat,
 		bpp = 4;
 		intFormat = GL_RGBA;
 		glFormat = GL_RGBA;
-		gltype = GL_UNSIGNED_BYTE;
+		gltype = GL_UNSIGNED_INT_8_8_8_8;
 	} else if (pixelFormat == Graphics::PixelFormat(3, 8, 8, 8, 0, 16, 8, 0, 0)) { // RGB888
 		bpp = 3;
 		intFormat = GL_RGB;
@@ -918,11 +918,6 @@ void OpenGLGraphicsManager::getGLPixelFormat(Graphics::PixelFormat pixelFormat,
 		intFormat = GL_RGBA;
 		glFormat = GL_RGBA;
 		gltype = GL_UNSIGNED_SHORT_5_5_5_1;
-	} else if (pixelFormat == Graphics::PixelFormat(2, 5, 5, 5, 0, 10, 5, 0, 0)) { // RGB555
-		bpp = 2;
-		intFormat = GL_RGB;
-		glFormat = GL_BGRA;
-		gltype = GL_UNSIGNED_SHORT_1_5_5_5_REV;
 	} else if (pixelFormat == Graphics::PixelFormat(2, 4, 4, 4, 4, 12, 8, 4, 0)) { // RGBA4444
 		bpp = 2;
 		intFormat = GL_RGBA;
@@ -936,6 +931,13 @@ void OpenGLGraphicsManager::getGLPixelFormat(Graphics::PixelFormat pixelFormat,
 		glFormat = GL_RGB;
 		gltype = GL_UNSIGNED_BYTE;
 #ifndef USE_GLES
+	} else if (pixelFormat == Graphics::PixelFormat(2, 5, 5, 5, 0, 10, 5, 0, 0)) { // RGB555
+		// GL_BGRA does not exist in every GLES implementation so should not be configured if
+		// USE_GLES is set.
+		bpp = 2;
+		intFormat = GL_RGB;
+		glFormat = GL_BGRA;
+		gltype = GL_UNSIGNED_SHORT_1_5_5_5_REV;
 	} else if (pixelFormat == Graphics::PixelFormat(4, 8, 8, 8, 8, 16, 8, 0, 24)) { // ARGB8888
 		bpp = 4;
 		intFormat = GL_RGBA;