RenderCopyEx,rotation and flipping for all hardware/software backends…

… (#1308)
libsdl-org · Jun 1, 2012 · 1b873da · 1b873da
1 parent fc741e4
commit 1b873da
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Showing 14 changed files with 1,549 additions and 9 deletions.
diff --git a/include/SDL_render.h b/include/SDL_render.h
@@ -104,6 +104,16 @@ typedef enum
     SDL_TEXTUREMODULATE_ALPHA = 0x00000002     /**< srcA = srcA * alpha */
 } SDL_TextureModulate;
 
+/**
+ *  \brief Flip constants for SDL_RenderCopyEx
+ */
+typedef enum
+{
+    SDL_FLIP_NONE = 0x00000000,     /**< Do not flip */
+    SDL_FLIP_HORIZONTAL = 0x00000001,    /**< flip horizontally */
+    SDL_FLIP_VERTICAL = 0x00000002     /**< flip vertically */
+} SDL_RendererFlip;
+
 /**
  *  \brief A structure representing rendering state
  */
@@ -599,6 +609,27 @@ extern DECLSPEC int SDLCALL SDL_RenderCopy(SDL_Renderer * renderer,
                                            const SDL_Rect * srcrect,
                                            const SDL_Rect * dstrect);
 
+/**
+ *  \brief Copy a portion of the source texture to the current rendering target, rotating it by angle around the given center 
+ *
+ *  \param texture The source texture.
+ *  \param srcrect   A pointer to the source rectangle, or NULL for the entire
+ *                   texture.
+ *  \param dstrect   A pointer to the destination rectangle, or NULL for the
+ *                   entire rendering target.
+ *  \param angle    An angle in degrees that indicates the rotation that will be applied to dstrect
+ *  \param center   A pointer to a point indicating the point around which dstrect will be rotated (if NULL, rotation will be done aroud dstrect.w/2, dstrect.h/2)
+ *  \param flip     A SFL_Flip value stating which flipping actions should be performed on the texture
+ * 
+ *  \return 0 on success, or -1 on error
+ */
+extern DECLSPEC int SDLCALL SDL_RenderCopyEx(SDL_Renderer * renderer,
+                                           SDL_Texture * texture,
+                                           const SDL_Rect * srcrect,
+                                           const SDL_Rect * dstrect,
+                                           const double angle,
+                                           const SDL_Point *center,
+                                           const SDL_RendererFlip flip);
 
 /**
  *  \brief Read pixels from the current rendering target.

diff --git a/src/render/SDL_render.c b/src/render/SDL_render.c
@@ -1231,6 +1231,62 @@ SDL_RenderCopy(SDL_Renderer * renderer, SDL_Texture * texture,
                                 &real_dstrect);
 }
 
+
+int
+SDL_RenderCopyEx(SDL_Renderer * renderer, SDL_Texture * texture,
+               const SDL_Rect * srcrect, const SDL_Rect * dstrect,
+               const double angle, const SDL_Point *center, const SDL_RendererFlip flip)
+{
+    SDL_Window *window;
+    SDL_Rect real_srcrect, real_dstrect;
+    SDL_Point real_center;
+
+    CHECK_RENDERER_MAGIC(renderer, -1);
+    CHECK_TEXTURE_MAGIC(texture, -1);
+
+    if (renderer != texture->renderer) {
+        SDL_SetError("Texture was not created with this renderer");
+        return -1;
+    }
+    if (!renderer->RenderCopyEx) {
+        SDL_SetError("Renderer does not support RenderCopyEx");
+        return -1;
+    }
+
+    window = renderer->window;
+
+    real_srcrect.x = 0;
+    real_srcrect.y = 0;
+    real_srcrect.w = texture->w;
+    real_srcrect.h = texture->h;
+    if (srcrect) {
+        if (!SDL_IntersectRect(srcrect, &real_srcrect, &real_srcrect)) {
+            return 0;
+        }
+    }
+
+    /* We don't intersect the dstrect with the viewport as RenderCopy does because of potential rotation clipping issues... TODO: should we? */
+    if (dstrect) real_dstrect = *dstrect;
+    else {
+        real_srcrect.x = 0;
+        real_srcrect.y = 0;
+        real_srcrect.w = renderer->viewport.w;
+        real_srcrect.h = renderer->viewport.h;
+    }
+
+    if (texture->native) {
+        texture = texture->native;
+    }
+
+    if(center) real_center = *center;
+    else {
+        real_center.x = real_dstrect.w/2;
+        real_center.y = real_dstrect.h/2;
+    }
+
+    return renderer->RenderCopyEx(renderer, texture, &real_srcrect, &real_dstrect, angle, &real_center, flip);
+}
+
 int
 SDL_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,
                      Uint32 format, void * pixels, int pitch)

diff --git a/src/render/SDL_sysrender.h b/src/render/SDL_sysrender.h
@@ -88,6 +88,9 @@ struct SDL_Renderer
                             int count);
     int (*RenderCopy) (SDL_Renderer * renderer, SDL_Texture * texture,
                        const SDL_Rect * srcrect, const SDL_Rect * dstrect);
+    int (*RenderCopyEx) (SDL_Renderer * renderer, SDL_Texture * texture,
+                       const SDL_Rect * srcquad, const SDL_Rect * dstrect,
+                       const double angle, const SDL_Point *center, const SDL_RendererFlip flip);
     int (*RenderReadPixels) (SDL_Renderer * renderer, const SDL_Rect * rect,
                              Uint32 format, void * pixels, int pitch);
     void (*RenderPresent) (SDL_Renderer * renderer);