/// Get the dimensions of a camera on the actual
// screen. It usually fills the whole window (= the full size of the
// resolution you specified in @{blitwizard.graphics.setMode}),
// but that may be changed with
// @{blitwizard.graphics.camera:setPixelDimensionsOnScreen|
// camera:setPixelDimensionsOnScreen}.
// @function getPixelDimensionsOnScreen
// @treturn number width Width of the camera on the screen in pixels
// @treturn number height Height of the camera on the screen in pixels
int luafuncs_camera_getPixelDimensionsOnScreen(lua_State* l) {
struct luacameralistentry* e = toluacameralistentry(
l, 1, 0, "blitwizard.graphics.camera:getPixelDimensionsOnScreen");
lua_pushnumber(l, graphics_getCameraWidth(e->cameraslot));
lua_pushnumber(l, graphics_getCameraHeight(e->cameraslot));
return 2;
}
/// Get the size of the camera in game units (so the size of the
// visible world area it shows).
//
// consider_zoom = false gives you the area of
// @{blitwizard.object:pinToCamera|pinned objects} which the camera
// shows, which is not influenced by zoom. (this is the default if
// consider_zoom is no specified at all)
//
// consider_zoom = true is a special case useful for 2d,
// which gives you the camera's dimensions according to the current
// zoom factor.
//
// The result of this function depends on the camera's
// @{blitwizard.graphics.camera:getPixelDimensionsOnScreen|
// actual size in pixels on the screen}, the camera's
// @{blitwizard.graphics.camera:get2dZoomFactor|
// 2d zoom factor} (for consider_zoom set to true) and the camera's
// @{blitwizard.graphics.camera:get2dAspectRatio|
// 2d aspect ratio}.
//
// <i>Note on @{blitwizard.object:pinToCamera|pinned} 2d objects:</i>
// If you want to know the area visible in game units for
// @{blitwizard.object:pinToCamera|pinned objects} which are unaffected
// by camera zoom when drawn, specify <i>false</i> as first parameter
// for not taking the zoom into account.
// @function getDimensions
// @tparam boolean consider_zoom (optional) defaults to false.
// Specifies whether the 2d zoom factor should be taken into account.
// Set to <i>true</i> if yes, <i>false</i> if not.
// @treturn number width the width of the camera in game units
// @treturn number height the height of the camera in game units
int luafuncs_camera_getDimensions(lua_State* l) {
struct luacameralistentry* e = toluacameralistentry(
l, 1, 0, "blitwizard.graphics.camera:getDimensions");
// if the camera default unit -> pixel conversion size isn't known yet:
if (!unittopixelsset) {
return haveluaerror(l, "this function is unavailable before the "
"first blitwizard.graphics.setMode call");
}
int considerzoom = 0;
// get consider_zoom parameter:
if (lua_gettop(l) >= 2 && lua_type(l, 2) != LUA_TNIL) {
if (lua_type(l, 2) != LUA_TBOOLEAN) {
return haveluaerror(l, badargument1, 1,
"blitwizard.graphics.camera:"
"getDimensions", "boolean", lua_strtype(l, 2));
}
considerzoom = lua_toboolean(l, 2);
}
// return visible area dimensions:
// FIXME: take aspect ratio into account once it can be changed
double w = graphics_getCameraWidth(e->cameraslot);
double h = graphics_getCameraHeight(e->cameraslot);
double z = graphics_getCamera2DZoom(e->cameraslot);
if (!considerzoom) {
z = 1;
}
lua_pushnumber(l, (w/UNIT_TO_PIXELS) * z);
lua_pushnumber(l, (h/UNIT_TO_PIXELS) * z);
return 2;
}
/// Specify a 2d position in the range from 0,0 to
// w,h with w,h being the camera visible area size
// as from @{blitwizard.graphics.camera:getDimensions|
// getDimensions} with consider_zoom set to <b>false</b>.
//
// (So the position you specify is the coordinates a
// @{blitwizard.object:pinToCamera|pinned object} would have on screen
// or the coordinates you get from @{blitwizard.onMouseMove})
//
// The position can also be smaller than 0,0 or larger than the
// actual camera dimensions, in which case you'll get an out-of-screen
// world position as a result.
// @function screenPosTo2dWorldPos
// @tparam number pos_x the X coordinate of the screen position
// @tparam number pos_y the Y coordinate of the screen position
// @tparam number parallax (optional) if you want, specify the @{blitwizard.object:setParallax|parallax} effect strength to get the world position displaced accordingly for an object with that parallax effect strength
// @treturn number X coordinate of the resulting world position
// @treturn number Y coordinate of the resulting world position
int luafuncs_camera_screenPosTo2dWorldPos(lua_State* l) {
struct luacameralistentry* e = toluacameralistentry(
l, 1, 0, "blitwizard.graphics.camera:screenPosTo2dWorldPos");
if (lua_type(l, 2) != LUA_TNUMBER) {
return haveluaerror(l, badargument1, 1,
"blitwizard.graphics.camera:screenPosTo2dWorldPos", "number", lua_strtype(l, 2));
}
if (lua_type(l, 3) != LUA_TNUMBER) {
return haveluaerror(l, badargument1, 2,
"blitwizard.graphics.camera:screenPosTo2dWorldPos", "number", lua_strtype(l, 3));
}
double parallax = 1;
if (lua_gettop(l) >= 4 && lua_type(l, 4) != LUA_TNIL) {
if (lua_type(l, 4) != LUA_TNUMBER) {
return haveluaerror(l, badargument1, 3,
"blitwizard.graphics.camera:screenPosTo2dWorldPos", "number", lua_strtype(l, 4));
}
if (lua_tonumber(l, 4) <= 0) {
return haveluaerror(l, badargument2, 3,
"blitwizard.graphics.camera:screenPosTo2dWorldPos",
"parallax effect strength needs to be greater than zero");
}
parallax = lua_tonumber(l, 4);
}
double x = lua_tonumber(l, 2);
double y = lua_tonumber(l, 3);
// calculate camera top left world position:
double tx = graphics_getCamera2DCenterX(e->cameraslot);
double ty = graphics_getCamera2DCenterY(e->cameraslot);
double zoomscale =
(UNIT_TO_PIXELS * graphics_getCamera2DZoom(e->cameraslot))
/ (double)UNIT_TO_PIXELS_DEFAULT;
double cameraWidth = graphics_getCameraWidth(e->cameraslot)
/ (double)UNIT_TO_PIXELS;
double cameraHeight = graphics_getCameraHeight(e->cameraslot)
/ (double)UNIT_TO_PIXELS;
tx -= (cameraWidth / zoomscale) * 0.5f;
ty -= (cameraHeight / zoomscale) * 0.5f;
// apply parallax effect as desired with screen center as parallax center:
x -= cameraWidth / 2;
y -= cameraHeight / 2;
x /= parallax;
y /= parallax;
x += cameraWidth / 2;
y += cameraHeight / 2;
// the onscreen coordinates need to be translated into "zoomed" space:
x /= graphics_getCamera2DZoom(e->cameraslot);
y /= graphics_getCamera2DZoom(e->cameraslot);
lua_pushnumber(l, tx + x);
lua_pushnumber(l, ty + y);
return 2;
}
void graphicsrender_draw(void) {
graphicssdlrender_startFrame();
graphics2dsprites_lockListOrTreeAccess();
// render world sprites:
double w = graphics_getCameraWidth(0);
double h = graphics_getCameraHeight(0);
double z = graphics_getCamera2DZoom(0);
double cwidth = (w/UNIT_TO_PIXELS) * z;
double cheight = (w/UNIT_TO_PIXELS) * z;
double ctopleftx = graphics_getCamera2DCenterX(0) - cwidth/2;
double ctoplefty = graphics_getCamera2DCenterY(0) - cheight/2;
graphics2dspritestree_doForAllSpritesSortedBottomToTop(
ctopleftx, ctoplefty, cwidth, cheight,
&graphicssdlrender_spriteCallback, NULL);
// render camera-pinned sprites:
graphics2dspriteslist_doForAllSpritesBottomToTop(
&graphicssdlrender_spriteCallback, NULL);
graphics2dsprites_releaseListOrTreeAccess();
graphicssdlrender_completeFrame();
}
