source: downloads/RenderSystems/GL/src/nvparse/rc1.0_general.cpp @ 3

#include "rc1.0_general.h"
#include "nvparse_errors.h"
#include "nvparse_externs.h"
#include <stdio.h>

#include <OgreGLPrerequisites.h>

void GeneralCombinersStruct::Validate(int numConsts, ConstColorStruct *pcc)
{
        GLint maxGCs;
        glGetIntegerv(GL_MAX_GENERAL_COMBINERS_NV, &maxGCs);
        if (num > maxGCs) {
                char buffer[256];
                sprintf(buffer, "%d general combiners specified, only %d supported", num, (int)maxGCs);
                errors.set(buffer);
                num = maxGCs;
        }

        if (0 == num) {
                // Setup a "fake" general combiner 0
                general[0].ZeroOut();
                num = 1;
        }

        localConsts = 0;
        int i;
        for (i = 0; i < num; i++)
                localConsts += general[i].numConsts;

        if (localConsts > 0)
                if (NULL == glCombinerStageParameterfvNV)
                        errors.set("local constant(s) specified, but not supported -- ignored");
                else
                        for (i = 0; i < num; i++)
                                general[i].SetUnusedLocalConsts(numConsts, pcc);

        for (i = 0; i < num; i++)
                general[i].Validate(i);


        for (; i < maxGCs; i++)
                general[i].ZeroOut();
}

void GeneralCombinersStruct::Invoke()
{
        glCombinerParameteriNV(GL_NUM_GENERAL_COMBINERS_NV, num);
        int i;
        for (i = 0; i < num; i++)
                general[i].Invoke(i);
        
        if (NULL != glCombinerStageParameterfvNV) {
                if (localConsts > 0)
                        glEnable(GL_PER_STAGE_CONSTANTS_NV);
                else
                        glDisable(GL_PER_STAGE_CONSTANTS_NV);
        }
                
}

void GeneralCombinerStruct::ZeroOut()
{
                numPortions = 2;
                numConsts = 0;

                portion[0].ZeroOut();
                portion[0].designator = RCP_RGB;
                portion[1].ZeroOut();
                portion[1].designator = RCP_ALPHA;
}


void GeneralCombinerStruct::SetUnusedLocalConsts(int numGlobalConsts, ConstColorStruct *globalCCs)
{
        int i;
        for (i = 0; i < numGlobalConsts; i++) {
                bool constUsed = false;
                int j;
                for (j = 0; j < numConsts; j++)
                        constUsed |= (cc[j].reg.bits.name == globalCCs[i].reg.bits.name);
                if (!constUsed)
                        cc[numConsts++] = globalCCs[i];
        }
}


void GeneralCombinerStruct::Validate(int stage)
{
        if (2 == numConsts &&
                cc[0].reg.bits.name == cc[1].reg.bits.name)
                errors.set("local constant set twice");

        switch (numPortions)
        {
        case 0:
                portion[0].designator = RCP_RGB;
                // Fallthru
        case 1:
                portion[1].designator = ((RCP_RGB == portion[0].designator) ? RCP_ALPHA : RCP_RGB);
                // Fallthru
        case 2:
                if (portion[0].designator == portion[1].designator)
                        errors.set("portion declared twice");
                break;
        }
        int i;
        for (i = 0; i < numPortions; i++)
                portion[i].Validate(stage);

        for (; i < 2; i++)
                portion[i].ZeroOut();

}

void GeneralCombinerStruct::Invoke(int stage)
{
        int i;

        if (NULL != glCombinerStageParameterfvNV)
                for (i = 0; i < numConsts; i++)
                        glCombinerStageParameterfvNV(GL_COMBINER0_NV + stage, cc[i].reg.bits.name, &(cc[i].v[0]));

        for (i = 0; i < 2; i++)
                portion[i].Invoke(stage);
}

void GeneralPortionStruct::Validate(int stage)
{
        gf.Validate(stage, designator);
}

void GeneralPortionStruct::Invoke(int stage)
{
        gf.Invoke(stage, designator, bs);
}

void GeneralPortionStruct::ZeroOut()
{
        gf.ZeroOut();
        bs.word = RCP_SCALE_BY_ONE;
}

void GeneralFunctionStruct::ZeroOut()
{
        // Create mapped registers for zero and discard
        MappedRegisterStruct unsignedZero;
        RegisterEnum zero;
        zero.word = RCP_ZERO;
        unsignedZero.Init(zero);

        MappedRegisterStruct unsignedDiscard;
        RegisterEnum discard;
        discard.word = RCP_DISCARD;
        unsignedDiscard.Init(discard);

        numOps = 3;

        op[0].op = RCP_MUL;
        op[0].reg[0] = unsignedDiscard;
        op[0].reg[1] = unsignedZero;
        op[0].reg[2] = unsignedZero;

        op[1].op = RCP_MUL;
        op[1].reg[0] = unsignedDiscard;
        op[1].reg[1] = unsignedZero;
        op[1].reg[2] = unsignedZero;

        op[2].op = RCP_SUM;
        op[2].reg[0] = unsignedDiscard;

}

void GeneralFunctionStruct::Validate(int stage, int portion)
{
        int i;
        for (i = 0; i < numOps; i++)
                op[i].Validate(stage, portion);
        // Check if multiple ops are writing to same register (and it's not DISCARD)
        if (numOps > 1 &&
                op[0].reg[0].reg.bits.name == op[1].reg[0].reg.bits.name &&
                GL_DISCARD_NV != op[0].reg[0].reg.bits.name)
                errors.set("writing to same register twice");
        if (numOps > 2 &&
                (op[0].reg[0].reg.bits.name == op[2].reg[0].reg.bits.name ||
                 op[1].reg[0].reg.bits.name == op[2].reg[0].reg.bits.name) &&
                GL_DISCARD_NV != op[2].reg[0].reg.bits.name)
                errors.set("writing to same register twice");

        // Set unused outputs to discard, unused inputs to zero/unsigned_identity
        if (numOps < 2) {
                // Set C input to zero
                op[1].reg[1].reg.bits.name = GL_ZERO;
                op[1].reg[1].map = GL_UNSIGNED_IDENTITY_NV;
                op[1].reg[1].reg.bits.channel = portion;

                // Set D input to zero
                op[1].reg[2].reg.bits.name = GL_ZERO;
                op[1].reg[2].map = GL_UNSIGNED_IDENTITY_NV;
                op[1].reg[2].reg.bits.channel = portion;

                // Discard CD output
                op[1].op = false;
                op[1].reg[0].reg.bits.name = GL_DISCARD_NV;
        }

        if (numOps < 3) {
                // Discard muxSum output
                op[2].reg[0].reg.bits.name = GL_DISCARD_NV;
                op[2].op = RCP_SUM;
        }
}


void GeneralFunctionStruct::Invoke(int stage, int portion, BiasScaleEnum bs)
{
        GLenum portionEnum = (RCP_RGB == portion) ? GL_RGB : GL_ALPHA;

        glCombinerInputNV(GL_COMBINER0_NV + stage,
                portionEnum,
                GL_VARIABLE_A_NV,
                op[0].reg[1].reg.bits.name,
                op[0].reg[1].map,
                MAP_CHANNEL(op[0].reg[1].reg.bits.channel));

        glCombinerInputNV(GL_COMBINER0_NV + stage,
                portionEnum,
                GL_VARIABLE_B_NV,
                op[0].reg[2].reg.bits.name,
                op[0].reg[2].map,
                MAP_CHANNEL(op[0].reg[2].reg.bits.channel));

        glCombinerInputNV(GL_COMBINER0_NV + stage,
                portionEnum,
                GL_VARIABLE_C_NV,
                op[1].reg[1].reg.bits.name,
                op[1].reg[1].map,
                MAP_CHANNEL(op[1].reg[1].reg.bits.channel));

        glCombinerInputNV(GL_COMBINER0_NV + stage,
                portionEnum,
                GL_VARIABLE_D_NV,
                op[1].reg[2].reg.bits.name,
                op[1].reg[2].map,
                MAP_CHANNEL(op[1].reg[2].reg.bits.channel));

        glCombinerOutputNV(GL_COMBINER0_NV + stage,
                portionEnum,
                op[0].reg[0].reg.bits.name,
                op[1].reg[0].reg.bits.name,
                op[2].reg[0].reg.bits.name,
                bs.bits.scale,
                bs.bits.bias,
                op[0].op,
                op[1].op,
                (op[2].op == RCP_MUX) ? true : false);
}

// This helper function assigns a channel to an undesignated input register
static void ConvertRegister(RegisterEnum& reg, int portion)
{
        if (RCP_NONE == reg.bits.channel) {
                reg.bits.channel = portion;
                if (GL_FOG == reg.bits.name && RCP_ALPHA == portion)
                        // Special case where fog alpha is final only, but RGB is not
                        reg.bits.finalOnly = true;
        }
}


void OpStruct::Validate(int stage, int portion)
{
        int args = 1;

        if (RCP_DOT == op || RCP_MUL == op)
                args = 3;
        else
                args = 1;

        if (reg[0].reg.bits.readOnly)
                errors.set("writing to a read-only register");

        if (RCP_ALPHA == portion &&
                RCP_DOT == op)
                errors.set("dot used in alpha portion");
        int i;
        for (i = 0; i < args; i++) {
                ConvertRegister(reg[i].reg, portion);
                if (reg[i].reg.bits.finalOnly)
                        errors.set("final register used in general combiner");
                if (RCP_RGB == portion &&
                        RCP_BLUE == reg[i].reg.bits.channel)
                        errors.set("blue register used in rgb portion");
                if (RCP_ALPHA == portion &&
                        RCP_RGB == reg[i].reg.bits.channel)
                        errors.set("rgb register used in alpha portion");
                if (i > 0 &&
                        GL_DISCARD_NV == reg[i].reg.bits.name)
                        errors.set("reading from discard");
        }
}