SparrowPrimitives is for drawing primitives like triangles or quads (with and without texture), blitting or rotozooming of surfaces, lines, ellipses, rectangles and for everything it provides a zBuffer test and set. You have to understand the difference between your screen / window, which could be (but doesn’t have to!) provided by sparrowCore (spCreateWindow), and your target, which can be every surface. Every call from this file, draws to the target. This may be your screen - but have not to be! Every SDL Surface* could be the target.
Some words to the z Buffer: First of all. If you don’t want any z buffering or stuff like this, call spSetZSet (0); and spSetZTest (0); at beginning. Z-Buffers will be created and cached, but not used. Furthermore most calls will be faster, but you loose a lot of fun and possibilities and have to think harder about sorting and stuff. :-P But if you use it, keep in mind, that the nearest z value is 0 and the farest away z value is set by spSetZFar-spSetZNear and positive. In difference to sparrowRenderer, which operates in the 3D space, where the z value go from -spSetZNear to -spSetZFar and are automaticly set by the projection setup function! So always think about the system you use:
If Z-Test is enabled, a pixel with a greater z-value than an already drawn pixel will not be drawn, because the new pixel would be “deeper in the screen”.
Some words to the order of definition of edges of triangles and quads: It matter! You have to define the edges counterclockwise, if you activated culling with spSetCulling, which is nevertheless on at default!
C________B E.g. the triangle A(150,150) B(200,100) C(100,100) is
\ / is definied counterclockwise (z doesn't matter here)
\ / and will be drawn. The triangle C B A would *not* be
\ / drawn. ;-)
\/ The reason is to not draw not seeable triangles/quads
A of closed fields in the 3d space.Some words to colors, too: Even if I use 32 Bit values, the engine works only with 16 Bit colors, with the 5 bit red, 6 bit green and 5 bit blue. I just use 32 bit values, because it is faster as parameters. Otherwise the compiler always would convert 16 bit to 32 bit and the other direction. If the compiler “thinks”, that it is just 32 Bit, it is faster.
| sparrowPrimitives | SparrowPrimitives is for drawing primitives like triangles or quads (with and without texture), blitting or rotozooming of surfaces, lines, ellipses, rectangles and for everything it provides a zBuffer test and set. |
| SP_MAX_SCANLINES | That much scanlines will be cached at most in the parallel drawing thread |
| Setup and getter functions | These functions are for setting up all graphical stuff like the different per pixel tests (z, alpha, pattern), sets (z), other optional optimizations and also the Z-Buffer and it’s cache plus getting some pointers for faster direct access. |
| spInitPrimitives | Initializes some Look up tables and the zBufferCache. |
| spQuitPrimitives | Releases stuff and frees memory. |
| spGetOne_over_x_pointer | Returns a pointer/array of SP_ONE (65536) values of 1/x |
| spSelectRenderTarget | Selects the render surface. |
| spGetRenderTarget | Returns the render target. |
| spGetTargetPixel | Returns a pointer to the raw 16 bit pixel data. |
| spLockRenderTarget | Locks the RenderTarget. |
| spUnlockRenderTarget | Unlocks the RenderTarget. |
| spGetRenderTargetZBuffer | Returns a pointer to the zBuffer of the render target |
| spBindTexture | This texture will be used for all following draw operations with textures |
| spSetZTest | (De)Activates the Z test (default on). |
| spSetZSet | (De)Activates the Z set (default on). |
| spSetAlphaTest | (De)Activates the alpha test (default on). |
| spSetBlending | (De)Activates real blending. |
| spEmulateBlendingWithPattern | Decides, whether real blending (maybe slow) is used or an emulation of blending using pattern in a dithering like way. |
| spSetAffineTextureHack | The texture rendering is fast, but a bit wrong. |
| spSetCulling | (De)Activates culling. |
| spSetLineWidth | Sets the width of spLine calls. |
| spClearTarget | Clears the Rendertarget. |
| spSetZBufferCache | If you use many Render Targets every time you switch it, the old ZBuffer will be destroyed and a new one created, which is slow. |
| spReAllocateZBuffer | Reallocates the zBuffer. |
| spResetZBuffer | Resets the zBuffer with the farest value. |
| spSetHorizontalOrigin | Sets the horizontal origin of the Surface rectangle and ellipses functions. |
| spSetVerticalOrigin | Sets the vertical origin of the Surface rectangle and ellipses functions. |
| spSetFixedOrign | Sets a fixed origin like (32,32). |
| spGetHorizontalOrigin | Returns the horizontal origin. |
| spGetVerticalOrigin | Returns the vertical origin. |
| spSetZFar | Sets the value, to which the zbuffer will be reseted. |
| spGetZFar | Gets the value, to which the zbuffer will be reseted. |
| spSetZNear | Sets the value, to which the zbuffer will be reseted. |
| spGetZNear | Gets the value, to which the zbuffer will be reseted. |
| spGetPixelPosition | Returns where the pixel is in relation to the screen. |
| Drawing functions | All these functions use (optional) z test, z set, alpha test and pattern test except spHorizentalLine, <spAddWhiteLayer> and <spAddBlackLayer> |
| spTriangle | Draws a colored Triangle. |
| spTriangle_tex | Draws a colored Triangle with texture mapping. |
| spPerspectiveTriangle_tex | Draws a colored Triangle with perspectively correct texture mapping. |
| spQuad | Draws a colored quad. |
| spQuad_tex | Draws a colored quad with texture mapping. |
| spPerspectiveQuad_tex | Draws a colored quad with perspectively correct texture mapping. |
| spBlitSurface | Draws a Surface on the target. |
| spBlitSurfacePart | Draws a part of a Surface on the target. |
| spRotozoomSurface | Draws a surface with rotozoom (Free rotating and zooming of the surface). |
| spRotozoomSurfacePart | Draws a part of a surface with rotozoom (Free rotating and zooming of the surface). |
| spLine | Draws a colored line |
| spRectangle | Draws a filled Rectangle. |
| spRectangleBorder | Draws a filled Rectangle border. |
| spEllipse | Draws a filled ellipse. |
| spEllipseBorder | Draws a filled ellipse border. |
| spHorizentalLine | Draws a fast horizental line with one color. |
| spAddColorToTarget | Adds a colored layer to the target surface. |
| spInterpolateTargetToColor | Interpolates the target to a color. |
| Pattern functions | sparrow3d does provide alpha blending (see spSetBlending), but this is slow, so use it rarely or better never. |
| spSetPattern32 | Sets the pattern with two 32 bit ints, each defines 4 lines |
| spSetPattern64 | Sets the pattern with two 64 bit int, it defines all 8 lines |
| spSetPattern8 | Sets the pattern with eight 8 bit ints line by line |
| spDeactivatePattern | Deactivates the pattern. |
| spSetAlphaPattern | Sets the pattern in dependence of an alpha value to “emulate” alpha blending. |
| spSetAlphaPattern4x4 | Works pretty like spSetAlphaPattern, but it uses 4x4 pattern internal. |
| spWaitForDrawingThread | If parallel processing of sparrowPrimitive is activated, this function waits until everything is drawn. |
| spDrawInExtraThread | Determines, whether an extra thread is used for drawing. |
| spUpdateTargetPixels | Updates the internal pixels pointer used by sparrow3d. |
| spFloodFill | Fills the target at the given position with a color using flood fill. |
PREFIX void spInitPrimitives( void )
Initializes some Look up tables and the zBufferCache. Is called by spInitCore.
PREFIX void spQuitPrimitives( void )
Releases stuff and frees memory. Is called by spQuitCore.
PREFIX void spSelectRenderTarget( SDL_Surface * target )
Selects the render surface. Attention: With every change of the target a new z Buffer is created or a cached is used. However, you can’t be sure of the content of the zbuffer after this call!
| target | the new target every draw call will render to. If NULL the target is set to Null, but the old target is unlocked. |
PREFIX Uint16* spGetTargetPixel( void )
Returns a pointer to the raw 16 bit pixel data. Keep in mind to change the zBuffer too, if you need it!
| Uint16* | 16 bit int pointer / array for free access. Keep the dimension of the array in mind, which is renderTarget->pitch/renderTarget->format->BytesPerPixel * renderTarget->h. |
PREFIX void spLockRenderTarget( void )
Locks the RenderTarget. Per default the target surface is locked all the time, so only call this function, if you called spUnlockRenderTarget before.
PREFIX void spUnlockRenderTarget( void )
Unlocks the RenderTarget. At default the sparrow3d targets are locked, so if you lock it e.g. for SDL calls, don’t forget to lock it afterwards with spLockRenderTarget.
PREFIX void spSetAlphaTest( Uint32 test )
(De)Activates the alpha test (default on). It tests against SP_ALPHA_COLOR.
| test | 1 means on, 0 means off |
PREFIX void spSetBlending( Sint32 value )
(De)Activates real blending. Every primitive, rectangle, ellipse, blitted or rotozoomed surface is blended. But keep in mind, that this is sloooow. Especially with rotozoom! Use it rarely or think about spSetAlphaPattern. On slower targets (e.g. the gp2x) at default blending is done via pattern emulation, see spEmulateBlendingWithPattern.
| value | 0 is total transparent, SP_ONE is total opaque. Everything in between will be blended. If value is SP_ONE internal no blending is done |
PREFIX void spEmulateBlendingWithPattern( Sint32 value )
Decides, whether real blending (maybe slow) is used or an emulation of blending using pattern in a dithering like way.
| value | 0 means no emulation is done, 1 (default) means, that emulation is done on slow systems like the gp2x and 2 means, that emulation is done all the time even on quite fast targets like the gcw zero. |
PREFIX void spSetAffineTextureHack( Uint32 test )
The texture rendering is fast, but a bit wrong. It is affine. To reduce this effect, which is best seeable with big, quadratic faces, activate this dirty hack. It could be a bit slower. Only affects Quads
| test | 0 deactivates this hack (default), 1 makes look it better and 2 the best. However most of the times you will not see any difference between 1 and 2 |
PREFIX void spSetCulling( char value )
(De)Activates culling. Culling means, that depending on the order of the edges, the primitive is drawn - or not. Default is on. That means: Every primitive defined counterclockwise will be drawn. That’s very important for Rendering meshes, because you can’t see the backside of a triangle or quad of an object. So why drawing it?
| value | 1 means on, 0 means off |
PREFIX void spSetLineWidth( Sint32 width )
Sets the width of spLine calls.
| width | the width of the line in pixel |
PREFIX void spSetZBufferCache( Uint32 value )
If you use many Render Targets every time you switch it, the old ZBuffer will be destroyed and a new one created, which is slow. So I implemented this caching. The engine will hold as much Z-Buffers as you say. Default: 16
| value | count of Z-Buffers to hold cached |
PREFIX void spSetHorizontalOrigin( Sint32 origin )
Sets the horizontal origin of the Surface rectangle and ellipses functions.
| origin | SP_LEFT for left origin, SP_RIGHT for right origin and SP_CENTER (default) for centered origin. Use SP_FIXED and spSetFixedOrign for a fixed origin. |
PREFIX void spSetVerticalOrigin( Sint32 origin )
Sets the vertical origin of the Surface rectangle and ellipses functions.
| origin | SP_TOP for top origin, SP_BOTTOM for bottom origin and SP_CENTER (default) for centered origin. Use SP_FIXED and spSetFixedOrign for a fixed origin. |
PREFIX void spSetFixedOrign( int x, int y )
Sets a fixed origin like (32,32). You have to pass SP_FIXED to spSetVerticalOrigin and spSetHorizontalOrigin.
| x,y | fixed pixel position of the origin. Default is (0,0). |
PREFIX void spSetZFar( Sint32 zfar )
Sets the value, to which the zbuffer will be reseted. Mostly called by spSetPerspective
| zfar | new farest value. Has to be positive |
PREFIX void spSetZNear( Sint32 znear )
Sets the value, to which the zbuffer will be reseted. Mostly called by spSetPerspective
| znear | new nearest value. Has to be positive |
All these functions use (optional) z test, z set, alpha test and pattern test except spHorizentalLine, <spAddWhiteLayer> and <spAddBlackLayer>
PREFIX int spTriangle( Sint32 x1, Sint32 y1, Sint32 z1, Sint32 x2, Sint32 y2, Sint32 z2, Sint32 x3, Sint32 y3, Sint32 z3, Uint32 color )
Draws a colored Triangle. The z value is interpolated over the triangle. Don’t forget to defines the edges counterclockwise if culling is enabled.
| x1,y1,z1 | position and z value of the first edge |
| x2,y2,z2 | position and z value of the second edge |
| x3,y3,z3 | position and z value of the third edge |
| color | 16 bit color of the whole triangle |
| int | 0 if not drawn (culling) or different bits, which define, where the edges are: 1 on screen, 2 left of screen, 4 lefttop, 8 top, 16 righttop, 32 right, 64 rightbottom, 128 bottom, 256 leftbottom |
PREFIX int spTriangle_tex( Sint32 x1, Sint32 y1, Sint32 z1, Sint32 u1, Sint32 v1, Sint32 x2, Sint32 y2, Sint32 z2, Sint32 u2, Sint32 v2, Sint32 x3, Sint32 y3, Sint32 z3, Sint32 u3, Sint32 v3, Uint32 color )
Draws a colored Triangle with texture mapping. The z value is interpolated over the triangle. Don’t forget to defines the edges counterclockwise if culling is enabled. Furthermore a texture had to be defined with spBindTexture.
| x1,y1,z1 | position and z value of the first edge |
| u1,v1 | texture coordinates of the first edge |
| x2,y2,z2 | position and z value of the second edge |
| u2,v2 | texture coordinates of the second edge |
| x3,y3,z3 | position and z value of the third edge |
| u3,v3 | texture coordinates of the third edge |
| color | 16 bit color of the whole triangle |
| int | 0 if not drawn (culling) or different bits, which define, where the edges are: 1 on screen, 2 left of screen, 4 lefttop, 8 top, 16 righttop, 32 right, 64 rightbottom, 128 bottom, 256 leftbottom |
PREFIX int spPerspectiveTriangle_tex( Sint32 x1, Sint32 y1, Sint32 z1, Sint32 u1, Sint32 v1, Sint32 w1, Sint32 x2, Sint32 y2, Sint32 z2, Sint32 u2, Sint32 v2, Sint32 w2, Sint32 x3, Sint32 y3, Sint32 z3, Sint32 u3, Sint32 v3, Sint32 w3, Uint32 color )
Draws a colored Triangle with perspectively correct texture mapping. The z value is interpolated over the triangle. Don’t forget to defines the edges counterclockwise if culling is enabled. Furthermore a texture had to be defined with spBindTexture.
| x1,y1,z1 | position and z value of the first edge |
| u1,v1 | texture coordinates of the first edge |
| w1 | w clipping ordinate of the first edge. It is a result of the projection. |
| x2,y2,z2 | position and z value of the second edge |
| u2,v2 | texture coordinates of the second edge |
| w2 | w clipping ordinate of the second edge. It is a result of the projection. |
| x3,y3,z3 | position and z value of the third edge |
| u3,v3 | texture coordinates of the third edge |
| w3 | w clipping ordinate of the third edge. It is a result of the projection. |
| color | 16 bit color of the whole triangle |
| int | 0 if not drawn (culling) or different bits, which define, where the edges are: 1 on screen, 2 left of screen, 4 lefttop, 8 top, 16 righttop, 32 right, 64 rightbottom, 128 bottom, 256 leftbottom |
PREFIX int spQuad( Sint32 x1, Sint32 y1, Sint32 z1, Sint32 x2, Sint32 y2, Sint32 z2, Sint32 x3, Sint32 y3, Sint32 z3, Sint32 x4, Sint32 y4, Sint32 z4, Uint32 color )
Draws a colored quad. The z value is interpolated over the quad. Don’t forget to defines the edges counterclockwise if culling is enabled.
| x1,y1,z1 | position and z value of the first edge |
| x2,y2,z2 | position and z value of the second edge |
| x3,y3,z3 | position and z value of the third edge |
| x4,y4,z4 | position and z value of the fourth edge |
| color | 16 bit color of the whole quad |
| int | 0 if not drawn (culling) or different bits, which define, where the edges are: 1 on screen, 2 left of screen, 4 lefttop, 8 top, 16 righttop, 32 right, 64 rightbottom, 128 bottom, 256 leftbottom |
PREFIX int spQuad_tex( Sint32 x1, Sint32 y1, Sint32 z1, Sint32 u1, Sint32 v1, Sint32 x2, Sint32 y2, Sint32 z2, Sint32 u2, Sint32 v2, Sint32 x3, Sint32 y3, Sint32 z3, Sint32 u3, Sint32 v3, Sint32 x4, Sint32 y4, Sint32 z4, Sint32 u4, Sint32 v4, Uint32 color )
Draws a colored quad with texture mapping. The z value is interpolated over the quad. Don’t forget to defines the edges counterclockwise if culling is enabled. Furthermore a texture had to be defined with spBindTexture.
| x1,y1,z1 | position and z value of the first edge |
| u1,v1 | texture coordinates of the first edge |
| x2,y2,z2 | position and z value of the second edge |
| u2,v2 | texture coordinates of the second edge |
| x3,y3,z3 | position and z value of the third edge |
| u3,v3 | texture coordinates of the third edge |
| x4,y4,z4 | position and z value of the fourth edge |
| u4,v4 | texture coordinates of the fourth edge |
| color | 16 bit color of the whole quad |
| int | 0 if not drawn (culling) or different bits, which define, where the edges are: 1 on screen, 2 left of screen, 4 lefttop, 8 top, 16 righttop, 32 right, 64 rightbottom, 128 bottom, 256 leftbottom |
PREFIX int spPerspectiveQuad_tex( Sint32 x1, Sint32 y1, Sint32 z1, Sint32 u1, Sint32 v1, Sint32 w1, Sint32 x2, Sint32 y2, Sint32 z2, Sint32 u2, Sint32 v2, Sint32 w2, Sint32 x3, Sint32 y3, Sint32 z3, Sint32 u3, Sint32 v3, Sint32 w3, Sint32 x4, Sint32 y4, Sint32 z4, Sint32 u4, Sint32 v4, Sint32 w4, Uint32 color )
Draws a colored quad with perspectively correct texture mapping. The z value is interpolated over the quad. Don’t forget to defines the edges counterclockwise if culling is enabled. Furthermore a texture had to be defined with spBindTexture.
| x1,y1,z1 | position and z value of the first edge |
| u1,v1 | texture coordinates of the first edge |
| w1 | w clipping ordinate of the first edge. It is a result of the projection. |
| x2,y2,z2 | position and z value of the second edge |
| u2,v2 | texture coordinates of the second edge |
| w2 | w clipping ordinate of the second edge. It is a result of the projection. |
| x3,y3,z3 | position and z value of the third edge |
| u3,v3 | texture coordinates of the third edge |
| w3 | w clipping ordinate of the third edge. It is a result of the projection. |
| x4,y4,z4 | position and z value of the fourth edge |
| u4,v4 | texture coordinates of the fourth edge |
| w4 | w clipping ordinate of the fourth edge. It is a result of the projection. |
| color | 16 bit color of the whole quad |
| int | 0 if not drawn (culling) or different bits, which define, where the edges are: 1 on screen, 2 left of screen, 4 lefttop, 8 top, 16 righttop, 32 right, 64 rightbottom, 128 bottom, 256 leftbottom |
PREFIX void spBlitSurface( Sint32 x, Sint32 y, Sint32 z, SDL_Surface * surface )
Draws a Surface on the target. The origin is at the center as default. Use spSetHorizontalOrigin and spSetVerticalOrigin to change this behaviour.
| x,y,z | position and z value, where to draw. |
| surface | the surface to draw |
PREFIX void spBlitSurfacePart( Sint32 x, Sint32 y, Sint32 z, SDL_Surface * surface, Sint32 sx, Sint32 sy, Sint32 w, Sint32 h )
Draws a part of a Surface on the target. The origin is at the center as default. Use spSetHorizontalOrigin and spSetVerticalOrigin to change this behaviour.
| x,y,z | position and z value, where to draw. |
| surface | the surface to draw |
| sx,sy | position of the left top corner of the part of the surface to be drawn |
| w,h | size of the part to be drawn |
PREFIX void spRotozoomSurface( Sint32 x, Sint32 y, Sint32 z, SDL_Surface * surface, Sint32 zoomX, Sint32 zoomY, Sint32 angle )
Draws a surface with rotozoom (Free rotating and zooming of the surface). Blitting with spBlitSurface is much faster ;-).
| x,y,z | position and z value of the surface on the target |
| surface | surface, which shall be rotozoomed |
| zoomX,zoomY | x and y zoom of the surface. These are fixed point factors, which means, that SP_ONE does nothing, a smaller value decreases and a bigger one increases the size |
| angle | fixed point radian value for rotating. Goes from 0 to 2*SP_PI |
PREFIX void spRotozoomSurfacePart( Sint32 x, Sint32 y, Sint32 z, SDL_Surface * surface, Sint32 sx, Sint32 sy, Sint32 w, Sint32 h, Sint32 zoomX, Sint32 zoomY, Sint32 angle )
Draws a part of a surface with rotozoom (Free rotating and zooming of the surface). Blitting with spBlitSurfacePart is much faster ;-).
| x,y,z | position and z value of the surface on the target |
| surface | surface, which shall be rotozoomed |
| sx,sy | position of the left top corner of the part of the surface to be drawn |
| w,h | size of the part to be drawn |
| zoomX,zoomY | x and y zoom of the surface. These are fixed point factors, which means, that SP_ONE does nothing, a smaller value decreases and a bigger one increases the size |
| angle | fixed point radian value for rotating. Goes from 0 to 2*SP_PI |
PREFIX void spRectangle( Sint32 x, Sint32 y, Sint32 z, Sint32 w, Sint32 h, Uint32 color )
Draws a filled Rectangle. The origin is at the center as default. Use spSetHorizontalOrigin and spSetVerticalOrigin to change this behaviour.
| x,y,z | position and z value, where to draw |
| w,h | size of the rectangle |
| color | 16 bit color of the whole rectangle |
PREFIX void spRectangleBorder( Sint32 x, Sint32 y, Sint32 z, Sint32 w, Sint32 h, Sint32 bx, Sint32 by, Uint32 color )
Draws a filled Rectangle border. The origin is at the center as default. Use spSetHorizontalOrigin and spSetVerticalOrigin to change this behaviour.
| x,y,z | position and z value, where to draw |
| w,h | size of the rectangle |
| bx,by | size of the border |
| color | 16 bit color of the whole rectangle border |
PREFIX void spEllipseBorder( Sint32 x, Sint32 y, Sint32 z, Sint32 rx, Sint32 ry, Sint32 bx, Sint32 by, Uint32 color )
Draws a filled ellipse border. The origin is at the center all the time.
| x,y,z | position and z value, where to draw |
| rx,ry | radii of the ellipse |
| bx,by | size of the border |
| color | 16 bit color of the whole ellipse |
PREFIX void spHorizentalLine( Uint16 * pixel, Sint32 x, Sint32 y, Sint32 l_, Uint32 color_, Uint32 check, Sint32 engineWindowX, Sint32 engineWindowY )
Draws a fast horizental line with one color. Don’t forget to lock your surface for this function! Use it e.g with spLockRenderTarget to get the pixel array and lock it automaticly. Because of some optimizations I can’t do this for you. If you are not sure, use spLine instead. No z test, z set, alpha test and pattern test!
| pixel | pointer to an Uint16 array of pixels |
| x,y | position of the line |
| l_ | length of the line (to the right) |
| color_ | 16 bit color value of the line |
| check | if 1 it will checked, whether the line reaches the end of the surface borders, with 0 no check happens |
| engineWindowX,engineWindowY | size of the pixel array |
PREFIX void spAddColorToTarget( Uint16 destColor, Sint32 interpolation )
Adds a colored layer to the target surface. Slow, but usefull for menu fade in and out. No z test, z set, alpha test and pattern test! If the color is brighter than white, it is clamped.
| destColor | color to add |
| interpolation | how many parts of destColor shall be added? 0 means nothing, SP_ONE all |
PREFIX void spInterpolateTargetToColor( Uint16 destColor, Sint32 interpolation )
Interpolates the target to a color. Slow, but usefull for menu fade in and out. No z test, z set, alpha test and pattern test!
| destColor | color to interpolate to |
| interpolation | how many parts of destColor shall be added? 0 means the target isn’t changed, with SP_ONE only destColor is left |
sparrow3d does provide alpha blending (see spSetBlending), but this is slow, so use it rarely or better never. However, with these three functions you can get some kind of much faster dithering alpha effect. In movement and on screens with a high dpi value it looks pretty good and is quite fast (as said before).
You setup a 8x8 1-bit-pattern (=64 bit), which is tested for as for z or alpha values. If the pattern-bit says 1, the pixel is drawn, if 0 it is not drawn. E.g. the mask
10101010 01010101 10101010 01010101 10101010 01010101 10101010 01010101
would make some kind of 50% alpha effect, because only 50% of the pixels are drawn.
PREFIX void spSetAlphaPattern( int alpha, int shift )
Sets the pattern in dependence of an alpha value to “emulate” alpha blending.
| alpha | the faked alpha value from 0 to 255 |
| shift | Shifting of the pattern, goes from 0 to 63. The problem is: Two primitives drawn with the same pattern (== same alpha and shift value) will cover each other, because exactly the same pixel will not be drawn. The alpha blending fake effect is gone. Solution: Using alpha simulation just a bit, using very different alpha values for covering primitives and using different shift values for every primitive, but for better look use for every single primitive in every frame the same shifting value, else it will look shitty. |
PREFIX void spSetAlphaPattern4x4( int alpha, int shift )
Works pretty like spSetAlphaPattern, but it uses 4x4 pattern internal. So there are only 16 different “alpha values”, but it looks better most of the time. (And I think it is faster, too.)
| alpha | still goes from 0 to 255, nevertheless only 16 value are used internal, so e.g the alpha value 3 and 7 are handeld the same way. |
| shift | goes only from 0 to 15, but works in the same way as in spSetAlphaPattern |
PREFIX void spWaitForDrawingThread( void )
If parallel processing of sparrowPrimitive is activated, this function waits until everything is drawn. If you want to draw stuff on your own, call this to be sure, that every change is done indeed! If no parallel processing is activated nothing happens.
PREFIX void spDrawInExtraThread( int value )
Determines, whether an extra thread is used for drawing. May be a bit slower (!) on systems with just one processor, but muuuuch faster on systems with at least two processors.
| value | 0 means no draw thread (default), 1 means an extra thread |
PREFIX void spUpdateTargetPixels( void )
Updates the internal pixels pointer used by sparrow3d. Used by spFlip for compatibility with Double- or even Triplebuffering.
Initializes some Look up tables and the zBufferCache.
PREFIX void spInitPrimitives( void )
Releases stuff and frees memory.
PREFIX void spQuitPrimitives( void )
Returns a pointer/array of SP_ONE (65536) values of 1/x
PREFIX Sint32* spGetOne_over_x_pointer( void )
Selects the render surface.
PREFIX void spSelectRenderTarget( SDL_Surface * target )
Returns the render target.
PREFIX SDL_Surface* spGetRenderTarget( void )
Returns a pointer to the raw 16 bit pixel data.
PREFIX Uint16* spGetTargetPixel( void )
Locks the RenderTarget.
PREFIX void spLockRenderTarget( void )
Unlocks the RenderTarget.
PREFIX void spUnlockRenderTarget( void )
Returns a pointer to the zBuffer of the render target
PREFIX Sint32* spGetRenderTargetZBuffer( void )
This texture will be used for all following draw operations with textures
PREFIX void spBindTexture( SDL_Surface * texture )
(De)Activates the Z test (default on).
PREFIX void spSetZTest( Uint32 test )
(De)Activates the Z set (default on).
PREFIX void spSetZSet( Uint32 test )
(De)Activates the alpha test (default on).
PREFIX void spSetAlphaTest( Uint32 test )
(De)Activates real blending.
PREFIX void spSetBlending( Sint32 value )
Decides, whether real blending (maybe slow) is used or an emulation of blending using pattern in a dithering like way.
PREFIX void spEmulateBlendingWithPattern( Sint32 value )
The texture rendering is fast, but a bit wrong.
PREFIX void spSetAffineTextureHack( Uint32 test )
(De)Activates culling.
PREFIX void spSetCulling( char value )
Sets the width of spLine calls.
PREFIX void spSetLineWidth( Sint32 width )
Draws a colored line
PREFIX void spLine( Sint32 x1, Sint32 y1, Sint32 z1, Sint32 x2, Sint32 y2, Sint32 z2, Uint32 color )
Clears the Rendertarget.
PREFIX void spClearTarget( Uint32 color )
If you use many Render Targets every time you switch it, the old ZBuffer will be destroyed and a new one created, which is slow.
PREFIX void spSetZBufferCache( Uint32 value )
Reallocates the zBuffer.
PREFIX void spReAllocateZBuffer( void )
Resets the zBuffer with the farest value.
PREFIX void spResetZBuffer( void )
Sets the horizontal origin of the Surface rectangle and ellipses functions.
PREFIX void spSetHorizontalOrigin( Sint32 origin )
Sets the vertical origin of the Surface rectangle and ellipses functions.
PREFIX void spSetVerticalOrigin( Sint32 origin )
Sets a fixed origin like (32,32).
PREFIX void spSetFixedOrign( int x, int y )
Returns the horizontal origin.
PREFIX Sint32 spGetHorizontalOrigin( void )
Returns the vertical origin.
PREFIX Sint32 spGetVerticalOrigin( void )
Sets the value, to which the zbuffer will be reseted.
PREFIX void spSetZFar( Sint32 zfar )
Gets the value, to which the zbuffer will be reseted.
PREFIX Sint32 spGetZFar( void )
Sets the value, to which the zbuffer will be reseted.
PREFIX void spSetZNear( Sint32 znear )
Gets the value, to which the zbuffer will be reseted.
PREFIX Sint32 spGetZNear( void )
Returns where the pixel is in relation to the screen.
PREFIX int spGetPixelPosition( Sint32 x, Sint32 y )
Draws a fast horizental line with one color.
PREFIX void spHorizentalLine( Uint16 * pixel, Sint32 x, Sint32 y, Sint32 l_, Uint32 color_, Uint32 check, Sint32 engineWindowX, Sint32 engineWindowY )
Draws a colored Triangle.
PREFIX int spTriangle( Sint32 x1, Sint32 y1, Sint32 z1, Sint32 x2, Sint32 y2, Sint32 z2, Sint32 x3, Sint32 y3, Sint32 z3, Uint32 color )
Draws a colored Triangle with texture mapping.
PREFIX int spTriangle_tex( Sint32 x1, Sint32 y1, Sint32 z1, Sint32 u1, Sint32 v1, Sint32 x2, Sint32 y2, Sint32 z2, Sint32 u2, Sint32 v2, Sint32 x3, Sint32 y3, Sint32 z3, Sint32 u3, Sint32 v3, Uint32 color )
Draws a colored Triangle with perspectively correct texture mapping.
PREFIX int spPerspectiveTriangle_tex( Sint32 x1, Sint32 y1, Sint32 z1, Sint32 u1, Sint32 v1, Sint32 w1, Sint32 x2, Sint32 y2, Sint32 z2, Sint32 u2, Sint32 v2, Sint32 w2, Sint32 x3, Sint32 y3, Sint32 z3, Sint32 u3, Sint32 v3, Sint32 w3, Uint32 color )
Draws a colored quad.
PREFIX int spQuad( Sint32 x1, Sint32 y1, Sint32 z1, Sint32 x2, Sint32 y2, Sint32 z2, Sint32 x3, Sint32 y3, Sint32 z3, Sint32 x4, Sint32 y4, Sint32 z4, Uint32 color )
Draws a colored quad with texture mapping.
PREFIX int spQuad_tex( Sint32 x1, Sint32 y1, Sint32 z1, Sint32 u1, Sint32 v1, Sint32 x2, Sint32 y2, Sint32 z2, Sint32 u2, Sint32 v2, Sint32 x3, Sint32 y3, Sint32 z3, Sint32 u3, Sint32 v3, Sint32 x4, Sint32 y4, Sint32 z4, Sint32 u4, Sint32 v4, Uint32 color )
Draws a colored quad with perspectively correct texture mapping.
PREFIX int spPerspectiveQuad_tex( Sint32 x1, Sint32 y1, Sint32 z1, Sint32 u1, Sint32 v1, Sint32 w1, Sint32 x2, Sint32 y2, Sint32 z2, Sint32 u2, Sint32 v2, Sint32 w2, Sint32 x3, Sint32 y3, Sint32 z3, Sint32 u3, Sint32 v3, Sint32 w3, Sint32 x4, Sint32 y4, Sint32 z4, Sint32 u4, Sint32 v4, Sint32 w4, Uint32 color )
Draws a Surface on the target.
PREFIX void spBlitSurface( Sint32 x, Sint32 y, Sint32 z, SDL_Surface * surface )
Draws a part of a Surface on the target.
PREFIX void spBlitSurfacePart( Sint32 x, Sint32 y, Sint32 z, SDL_Surface * surface, Sint32 sx, Sint32 sy, Sint32 w, Sint32 h )
Draws a surface with rotozoom (Free rotating and zooming of the surface).
PREFIX void spRotozoomSurface( Sint32 x, Sint32 y, Sint32 z, SDL_Surface * surface, Sint32 zoomX, Sint32 zoomY, Sint32 angle )
Draws a part of a surface with rotozoom (Free rotating and zooming of the surface).
PREFIX void spRotozoomSurfacePart( Sint32 x, Sint32 y, Sint32 z, SDL_Surface * surface, Sint32 sx, Sint32 sy, Sint32 w, Sint32 h, Sint32 zoomX, Sint32 zoomY, Sint32 angle )
Draws a filled Rectangle.
PREFIX void spRectangle( Sint32 x, Sint32 y, Sint32 z, Sint32 w, Sint32 h, Uint32 color )
Draws a filled Rectangle border.
PREFIX void spRectangleBorder( Sint32 x, Sint32 y, Sint32 z, Sint32 w, Sint32 h, Sint32 bx, Sint32 by, Uint32 color )
Draws a filled ellipse.
PREFIX void spEllipse( Sint32 x, Sint32 y, Sint32 z, Sint32 rx, Sint32 ry, Uint32 color )
Draws a filled ellipse border.
PREFIX void spEllipseBorder( Sint32 x, Sint32 y, Sint32 z, Sint32 rx, Sint32 ry, Sint32 bx, Sint32 by, Uint32 color )
Adds a colored layer to the target surface.
PREFIX void spAddColorToTarget( Uint16 destColor, Sint32 interpolation )
Interpolates the target to a color.
PREFIX void spInterpolateTargetToColor( Uint16 destColor, Sint32 interpolation )
Sets the pattern with two 32 bit ints, each defines 4 lines
PREFIX void spSetPattern32( Uint32 first_32_bit, Uint32 last_32_bit )
Sets the pattern with two 64 bit int, it defines all 8 lines
PREFIX void spSetPattern64( Uint64 pattern )
Sets the pattern with eight 8 bit ints line by line
PREFIX void spSetPattern8( Uint8 line1, Uint8 line2, Uint8 line3, Uint8 line4, Uint8 line5, Uint8 line6, Uint8 line7, Uint8 line8 )
Deactivates the pattern.
PREFIX void spDeactivatePattern( void )
Sets the pattern in dependence of an alpha value to “emulate” alpha blending.
PREFIX void spSetAlphaPattern( int alpha, int shift )
Works pretty like spSetAlphaPattern, but it uses 4x4 pattern internal.
PREFIX void spSetAlphaPattern4x4( int alpha, int shift )
If parallel processing of sparrowPrimitive is activated, this function waits until everything is drawn.
PREFIX void spWaitForDrawingThread( void )
Determines, whether an extra thread is used for drawing.
PREFIX void spDrawInExtraThread( int value )
Updates the internal pixels pointer used by sparrow3d.
PREFIX void spUpdateTargetPixels( void )
Fills the target at the given position with a color using flood fill.
PREFIX void spFloodFill( int x, int y, Uint16 color )
Creates the Window in the plattform depended resolution.
PREFIX SDL_Surface* spCreateWindow( int width, int height, int fullscreen, int allowresize )
Sets the projection matrix.
PREFIX void spSetPerspective( float fovyInDegrees, float aspectRatio, float znear, float zfar )
spInitCore initializes SDL, SDL_TTF and other stuff.
PREFIX void spInitCore( void )
Just quits the Core.
PREFIX void spQuitCore( void )
Draws the changes in the window Surface on the screen.
PREFIX void spFlip( void )