drawArrays.c

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#include "internal.h"
 
void C3D_DrawArrays(GPU_Primitive_t primitive, int first, int size)
{
    C3Di_UpdateContext();
 
    // Set primitive type
    GPUCMD_AddMaskedWrite(GPUREG_PRIMITIVE_CONFIG, 2, primitive);
    // Start a new primitive (breaks off a triangle strip/fan)
    GPUCMD_AddWrite(GPUREG_RESTART_PRIMITIVE, 1);
    // The index buffer is not used, but this command is still required
    GPUCMD_AddWrite(GPUREG_INDEXBUFFER_CONFIG, 0x80000000);
    // Number of vertices
    GPUCMD_AddWrite(GPUREG_NUMVERTICES, size);
    // First vertex
    GPUCMD_AddWrite(GPUREG_VERTEX_OFFSET, first);
    // Enable array drawing mode
    GPUCMD_AddMaskedWrite(GPUREG_GEOSTAGE_CONFIG2, 1, 1);
    // Enable drawing mode
    GPUCMD_AddMaskedWrite(GPUREG_START_DRAW_FUNC0, 1, 0);
    // Trigger array drawing
    GPUCMD_AddWrite(GPUREG_DRAWARRAYS, 1);
    // Go back to configuration mode
    GPUCMD_AddMaskedWrite(GPUREG_START_DRAW_FUNC0, 1, 1);
    // Disable array drawing mode
    GPUCMD_AddMaskedWrite(GPUREG_GEOSTAGE_CONFIG2, 1, 0);
    // Clear the post-vertex cache
    GPUCMD_AddWrite(GPUREG_VTX_FUNC, 1);
 
    C3Di_GetContext()->flags |= C3DiF_DrawUsed;
}