PowerVR Series1

Up QuickStart1 QuickStart2 QuickStart3 QuickStart4 QuickStart5 |  | ### PowerVR SGL Direct Quickstart Tutorial - Step 3
| The SGLCONTEXT structure includes parameters determining the environment, like for example background colour, texture mapping, shadows, etc. In this example we modify a few parameters in SGLContext to introduce some thick blue fog.
    #include "sgl.h"
    #define RGB(r, g, b) ((sgl_uint32) (((r) << 16) | ((g) << 8) | (b)))
    SGLCONTEXT SGLContext;
    SGLVERTEX  Vertices[] = {
                /* x      y     z   (1/W)    col       spec.col (u/W)(v/W)*/
    	    {  0.0f,240.0f,0.0f,0.1f,RGB(255,0,0),RGB(0,0,0),0.0f,0.0f},
    	    {320.0f,479.0f,0.0f,0.8f,RGB(255,0,0),RGB(0,0,0),0.0f,0.0f},
    	    {639.0f,240.0f,0.0f,0.1f,RGB(255,0,0),RGB(0,0,0),0.0f,0.0f},
                {320.0f,  0.0f,0.0f,0.8f,RGB(0,255,0),RGB(0,0,0),0.0f,0.0f}
    		        };
    int	   TriFaceData[][3] = {{0,1,2},{3,0,2}};
    int        Device;

    void main ()
    {
       Device = sgl_create_screen_device (0,640,480,sgl_device_16bit,TRUE);
       if (Device >= 0)
       {
          SGLContext.bFogOn=TRUE;
          SGLContext.fFogR=0.5f;
          SGLContext.fFogG=0.5f;
          SGLContext.fFogB=1.0f;
          SGLContext.u32FogDensity=16;
| This enables fog, and colours it blue (each R,G,B value ranges between 0 and 1, where 1 is maximum intensity. The fog density parameter ranges from 0 (no fog) to 31 (very thick fog).
          sgltri_startofframe (&SGLContext);
          sgltri_triangles    (&SGLContext, 2, TriFaceData, Vertices);
          sgltri_render       (&SGLContext);

          sgl_delete_device   (Device);
       }
    }
You may view this source code. Translating the triangle vertices will result in simple animation of the scene. Click here to see how it's done ... Go to PowerSGL Direct QuickStart Page 1 - 2 - 4 - 5

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