From d8d717ec3ff6db92165894d85b8593526ba0d37c Mon Sep 17 00:00:00 2001
From: Hermet Park <hermet@lottiefiles.com>
Date: Tue, 14 May 2024 15:33:26 +0900
Subject: [PATCH] capi: support canvas viewport api

New Experimental API:
- Tvg_Result tvg_canvas_set_viewport(Tvg_Canvas* canvas, int32_t x, int32_t y, int32_t w, int32_t h);
---
 src/bindings/capi/thorvg_capi.h | 26 +++++++++++++++++++++++++-
 src/bindings/capi/tvgCapi.cpp   |  7 +++++++
 2 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/src/bindings/capi/thorvg_capi.h b/src/bindings/capi/thorvg_capi.h
index 4dc27f70..a8451920 100644
--- a/src/bindings/capi/thorvg_capi.h
+++ b/src/bindings/capi/thorvg_capi.h
@@ -453,7 +453,7 @@ TVG_API Tvg_Canvas* tvg_swcanvas_create();
 * \retval TVG_RESULT_INVALID_ARGUMENTS An invalid canvas or buffer pointer passed or one of the @p stride, @p w or @p h being zero.
 * \retval TVG_RESULT_NOT_SUPPORTED The software engine is not supported.
 *
-* \warning Do not access @p buffer during tvg_canvas_draw() - tvg_canvas_sync(). It should not be accessed while TVG is writing on it.
+* \warning Do not access @p buffer during tvg_canvas_draw() - tvg_canvas_sync(). It should not be accessed while the engine is writing on it.
 *
 * \see Tvg_Colorspace
 */
@@ -743,6 +743,30 @@ TVG_API Tvg_Result tvg_canvas_draw(Tvg_Canvas* canvas);
 TVG_API Tvg_Result tvg_canvas_sync(Tvg_Canvas* canvas);
 
 
+/*!
+* \brief Sets the drawing region in the canvas.
+*
+* This function defines the rectangular area of the canvas that will be used for drawing operations.
+* The specified viewport is used to clip the rendering output to the boundaries of the rectangle.
+*
+* \param[in] canvas The Tvg_Canvas object containing elements which were drawn.
+* \param[in] x The x-coordinate of the upper-left corner of the rectangle.
+* \param[in] y The y-coordinate of the upper-left corner of the rectangle.
+* \param[in] w The width of the rectangle.
+* \param[in] h The height of the rectangle.
+*
+* \return Tvg_Result enumeration.
+* \retval TVG_RESULT_SUCCESS Succeed.
+* \retval TVG_RESULT_INSUFFICIENT_CONDITION An internal error.
+*
+* \warning It's not allowed to change the viewport during tvg_canvas_update() - tvg_canvas_sync() or tvg_canvas_push() - tvg_canvas_sync().
+*
+* \note The specified viewport region will be intersected with the target region.
+* \note Experimental API
+* \see tvg_swcanvas_set_target()
+*/
+TVG_API Tvg_Result tvg_canvas_set_viewport(Tvg_Canvas* canvas, int32_t x, int32_t y, int32_t w, int32_t h);
+
 /** \} */   // end defgroup ThorVGCapi_Canvas
 
 
diff --git a/src/bindings/capi/tvgCapi.cpp b/src/bindings/capi/tvgCapi.cpp
index 8aca4294..1c1acc2e 100644
--- a/src/bindings/capi/tvgCapi.cpp
+++ b/src/bindings/capi/tvgCapi.cpp
@@ -111,6 +111,13 @@ TVG_API Tvg_Result tvg_canvas_update(Tvg_Canvas* canvas)
 }
 
 
+TVG_API Tvg_Result tvg_canvas_est_viewport(Tvg_Canvas* canvas, int32_t x, int32_t y, int32_t w, int32_t h)
+{
+    if (!canvas) return TVG_RESULT_INVALID_ARGUMENT;
+    return (Tvg_Result) reinterpret_cast<Canvas*>(canvas)->viewport(x, y, w, h);
+}
+
+
 TVG_API Tvg_Result tvg_canvas_update_paint(Tvg_Canvas* canvas, Tvg_Paint* paint)
 {
     if (!canvas || !paint) return TVG_RESULT_INVALID_ARGUMENT;