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path: root/src/mesa/drivers/dri/mga/mga_texcombine.c
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Diffstat (limited to 'src/mesa/drivers/dri/mga/mga_texcombine.c')
-rw-r--r--src/mesa/drivers/dri/mga/mga_texcombine.c647
1 files changed, 647 insertions, 0 deletions
diff --git a/src/mesa/drivers/dri/mga/mga_texcombine.c b/src/mesa/drivers/dri/mga/mga_texcombine.c
new file mode 100644
index 0000000000..f0664e37cf
--- /dev/null
+++ b/src/mesa/drivers/dri/mga/mga_texcombine.c
@@ -0,0 +1,647 @@
+/*
+ * Copyright (c) 2003 Ville Syrjala
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Authors:
+ * Ville Syrjala <syrjala@sci.fi>
+ */
+
+#include "glheader.h"
+
+#include "mgacontext.h"
+#include "mgatex.h"
+#include "mgaregs.h"
+
+/*
+ * GL_ARB_texture_env_combine
+ * GL_EXT_texture_env_combine
+ * GL_ARB_texture_env_crossbar
+ * GL_ATI_texture_env_combine3
+ */
+
+#define ARG_DISABLE 0xffffffff
+#define MGA_ARG1 0
+#define MGA_ARG2 1
+#define MGA_ALPHA 2
+
+GLboolean mgaUpdateTextureEnvCombine( GLcontext *ctx, int unit )
+{
+ mgaContextPtr mmesa = MGA_CONTEXT(ctx);
+ const int source = mmesa->tmu_source[unit];
+ const struct gl_texture_unit *texUnit = &ctx->Texture.Unit[source];
+ GLuint *reg = ((GLuint *)&mmesa->setup.tdualstage0 + unit);
+ GLuint numColorArgs = 0, numAlphaArgs = 0;
+ GLuint arg1[3], arg2[3], alpha[3];
+ int args[3];
+ int i;
+
+ switch (texUnit->CombineModeRGB) {
+ case GL_REPLACE:
+ numColorArgs = 1;
+ break;
+ case GL_MODULATE:
+ case GL_ADD:
+ case GL_ADD_SIGNED:
+ case GL_SUBTRACT:
+ numColorArgs = 2;
+ break;
+ case GL_INTERPOLATE:
+ case GL_MODULATE_ADD_ATI:
+ case GL_MODULATE_SIGNED_ADD_ATI:
+ case GL_MODULATE_SUBTRACT_ATI:
+ numColorArgs = 3;
+ break;
+ default:
+ return GL_FALSE;
+ }
+
+ switch (texUnit->CombineModeA) {
+ case GL_REPLACE:
+ numAlphaArgs = 1;
+ break;
+ case GL_MODULATE:
+ case GL_ADD:
+ case GL_ADD_SIGNED:
+ case GL_SUBTRACT:
+ numAlphaArgs = 2;
+ break;
+ default:
+ return GL_FALSE;
+ }
+
+ /* Start fresh :) */
+ *reg = 0;
+
+ /* COLOR */
+ for (i = 0; i < 3; i++) {
+ arg1[i] = 0;
+ arg2[i] = 0;
+ alpha[i] = 0;
+ }
+
+ for (i = 0;i < numColorArgs; i++) {
+ switch (texUnit->CombineSourceRGB[i]) {
+ case GL_TEXTURE:
+ arg1[i] |= 0;
+ arg2[i] |= ARG_DISABLE;
+ alpha[i] |= TD0_color_alpha_currtex;
+ break;
+ case GL_TEXTURE0:
+ if (source == 0) {
+ arg1[i] |= 0;
+ arg2[i] |= ARG_DISABLE;
+ alpha[i] |= TD0_color_alpha_currtex;
+ } else {
+ if (ctx->Texture._EnabledUnits != 0x03) {
+ /* disable texturing */
+ mmesa->setup.dwgctl &= DC_opcod_MASK;
+ mmesa->setup.dwgctl |= DC_opcod_trap;
+ mmesa->hw.alpha_sel = AC_alphasel_diffused;
+ /* return GL_TRUE since we don't need a fallback */
+ return GL_TRUE;
+ }
+ arg1[i] |= ARG_DISABLE;
+ arg2[i] |= ARG_DISABLE;
+ alpha[i] |= TD0_color_alpha_prevtex;
+ }
+ break;
+ case GL_TEXTURE1:
+ if (source == 0) {
+ if (ctx->Texture._EnabledUnits != 0x03) {
+ /* disable texturing */
+ mmesa->setup.dwgctl &= DC_opcod_MASK;
+ mmesa->setup.dwgctl |= DC_opcod_trap;
+ mmesa->hw.alpha_sel = AC_alphasel_diffused;
+ /* return GL_TRUE since we don't need a fallback */
+ return GL_TRUE;
+ }
+ arg1[i] |= ARG_DISABLE;
+ /* G400 specs (TDUALSTAGE0) */
+ arg2[i] |= TD0_color_arg2_prevstage;
+ alpha[i] |= TD0_color_alpha_prevstage;
+ } else {
+ arg1[i] |= 0;
+ arg2[i] |= ARG_DISABLE;
+ alpha[i] |= TD0_color_alpha_currtex;
+ }
+ break;
+ case GL_CONSTANT:
+ arg1[i] |= ARG_DISABLE;
+ arg2[i] |= TD0_color_arg2_fcol;
+ alpha[i] |= TD0_color_alpha_fcol;
+ break;
+ case GL_PRIMARY_COLOR:
+ arg1[i] |= ARG_DISABLE;
+ /* G400 specs (TDUALSTAGE1) */
+ if (unit == 0 || (mmesa->setup.tdualstage0 &
+ ((TD0_color_sel_mul & TD0_color_sel_add) |
+ (TD0_alpha_sel_mul & TD0_alpha_sel_add)))) {
+ arg2[i] |= TD0_color_arg2_diffuse;
+ alpha[i] |= TD0_color_alpha_diffuse;
+ } else {
+ arg2[i] |= ARG_DISABLE;
+ alpha[i] |= ARG_DISABLE;
+ }
+ break;
+ case GL_PREVIOUS:
+ arg1[i] |= ARG_DISABLE;
+ if (unit == 0) {
+ arg2[i] |= TD0_color_arg2_diffuse;
+ alpha[i] |= TD0_color_alpha_diffuse;
+ } else {
+ arg2[i] |= TD0_color_arg2_prevstage;
+ alpha[i] |= TD0_color_alpha_prevstage;
+ }
+ break;
+ default:
+ return GL_FALSE;
+ }
+
+ switch (texUnit->CombineOperandRGB[i]) {
+ case GL_SRC_COLOR:
+ arg1[i] |= 0;
+ arg2[i] |= 0;
+ alpha[i] |= ARG_DISABLE;
+ break;
+ case GL_ONE_MINUS_SRC_COLOR:
+ arg1[i] |= TD0_color_arg1_inv_enable;
+ arg2[i] |= TD0_color_arg2_inv_enable;
+ alpha[i] |= ARG_DISABLE;
+ break;
+ case GL_SRC_ALPHA:
+ arg1[i] |= TD0_color_arg1_replicatealpha_enable;
+ arg2[i] |= TD0_color_arg2_replicatealpha_enable;
+ alpha[i] |= 0;
+ break;
+ case GL_ONE_MINUS_SRC_ALPHA:
+ arg1[i] |= (TD0_color_arg1_replicatealpha_enable |
+ TD0_color_arg1_inv_enable);
+ arg2[i] |= (TD0_color_arg2_replicatealpha_enable |
+ TD0_color_arg2_inv_enable);
+ alpha[i] |= (TD0_color_alpha1inv_enable |
+ TD0_color_alpha2inv_enable);
+ break;
+ }
+ }
+
+ switch (texUnit->CombineModeRGB) {
+ case GL_MODULATE_ADD_ATI:
+ case GL_MODULATE_SIGNED_ADD_ATI:
+ /* Special handling for ATI_texture_env_combine3.
+ * If Arg1 == Arg0 or Arg1 == Arg2 we can use arg1 or arg2 as input for
+ * both multiplier and adder.
+ */
+ /* Arg1 == arg1 */
+ if (arg1[1] == arg1[0]) {
+ if ((arg1[1] | arg2[2]) != ARG_DISABLE) {
+ *reg |= arg1[1] | arg2[2];
+ args[0] = MGA_ARG1; args[1] = MGA_ARG1; args[2] = MGA_ARG2;
+ break;
+ } else
+ if ((arg1[1] | alpha[2]) != ARG_DISABLE) {
+ *reg |= arg1[1] | alpha[2];
+ args[0] = MGA_ARG1; args[1] = MGA_ARG1; args[2] = MGA_ALPHA;
+ break;
+ }
+ }
+ if (arg1[1] == arg1[2]) {
+ if ((arg1[1] | arg2[0]) != ARG_DISABLE) {
+ *reg |= arg1[1] | arg2[0];
+ args[0] = MGA_ARG2; args[1] = MGA_ARG1; args[2] = MGA_ARG1;
+ break;
+ } else
+ if ((arg1[1] | alpha[0]) != ARG_DISABLE) {
+ *reg |= arg1[1] | alpha[0];
+ args[0] = MGA_ALPHA; args[1] = MGA_ARG1; args[2] = MGA_ARG1;
+ break;
+ }
+ }
+ /* fallthrough */
+ case GL_MODULATE_SUBTRACT_ATI:
+ /* Arg1 == arg2 */
+ if (arg2[1] == arg2[0]) {
+ if ((arg2[1] | arg1[2]) != ARG_DISABLE) {
+ *reg |= arg2[1] | arg1[2];
+ args[0] = MGA_ARG2; args[1] = MGA_ARG2; args[2] = MGA_ARG1;
+ break;
+ } else
+ if ((arg2[1] | alpha[2]) != ARG_DISABLE) {
+ *reg |= arg2[1] | alpha[2];
+ args[0] = MGA_ARG2; args[1] = MGA_ARG2; args[2] = MGA_ALPHA;
+ break;
+ }
+ }
+ if (arg2[1] == arg2[2]) {
+ if ((arg2[1] | arg1[0]) != ARG_DISABLE) {
+ *reg |= arg2[1] | arg1[0];
+ args[0] = MGA_ARG1; args[1] = MGA_ARG2; args[2] = MGA_ARG2;
+ break;
+ } else
+ if ((arg2[1] | alpha[0]) != ARG_DISABLE) {
+ *reg |= arg2[1] | alpha[0];
+ args[0] = MGA_ALPHA; args[1] = MGA_ARG2; args[2] = MGA_ARG2;
+ break;
+ }
+ }
+ /* fallthrough */
+ default:
+ /* Find working combo of arg1, arg2 and alpha.
+ *
+ * Keep the Arg0 != alpha cases first since there's
+ * no way to get alpha out by itself (GL_REPLACE).
+ *
+ * Keep the Arg2 == alpha cases first because only alpha has the
+ * capabilities to function as Arg2 (GL_INTERPOLATE). Also good for
+ * GL_ADD, GL_ADD_SIGNED, GL_SUBTRACT since we can't get alpha to the
+ * adder.
+ *
+ * Keep the Arg1 == alpha cases last for GL_MODULATE_ADD_ATI,
+ * GL_MODULATE_SIGNED_ADD_ATI. Again because we can't get alpha to the
+ * adder.
+ *
+ * GL_MODULATE_SUBTRACT_ATI needs special treatment since it requires
+ * that Arg1 == arg2. This requirement clashes with those of other modes.
+ */
+ if ((arg1[0] | arg2[1] | alpha[2]) != ARG_DISABLE) {
+ *reg |= arg1[0] | arg2[1] | alpha[2];
+ args[0] = MGA_ARG1; args[1] = MGA_ARG2; args[2] = MGA_ALPHA;
+ } else
+ if ((arg1[1] | arg2[0] | alpha[2]) != ARG_DISABLE &&
+ texUnit->CombineModeRGB != GL_MODULATE_SUBTRACT_ATI) {
+ *reg |= arg1[1] | arg2[0] | alpha[2];
+ args[0] = MGA_ARG2; args[1] = MGA_ARG1; args[2] = MGA_ALPHA;
+ } else
+ if ((arg1[1] | arg2[2] | alpha[0]) != ARG_DISABLE &&
+ texUnit->CombineModeRGB != GL_MODULATE_SUBTRACT_ATI) {
+ *reg |= arg1[1] | arg2[2] | alpha[0];
+ args[0] = MGA_ALPHA; args[1] = MGA_ARG1; args[2] = MGA_ARG2;
+ } else
+ if ((arg1[2] | arg2[1] | alpha[0]) != ARG_DISABLE) {
+ *reg |= arg1[2] | arg2[1] | alpha[0];
+ args[0] = MGA_ALPHA; args[1] = MGA_ARG2; args[2] = MGA_ARG1;
+ } else
+ if ((arg1[0] | arg2[2] | alpha[1]) != ARG_DISABLE) {
+ *reg |= arg1[0] | arg2[2] | alpha[1];
+ args[0] = MGA_ARG1; args[1] = MGA_ALPHA; args[2] = MGA_ARG2;
+ } else
+ if ((arg1[2] | arg2[0] | alpha[1]) != ARG_DISABLE) {
+ *reg |= arg1[2] | arg2[0] | alpha[1];
+ args[0] = MGA_ARG2; args[1] = MGA_ALPHA; args[2] = MGA_ARG1;
+ } else {
+ /* nothing suitable */
+ return GL_FALSE;
+ }
+ }
+
+ switch (texUnit->CombineModeRGB) {
+ case GL_REPLACE:
+ if (texUnit->CombineScaleShiftRGB) {
+ return GL_FALSE;
+ }
+
+ if (args[0] == MGA_ARG1) {
+ *reg |= TD0_color_sel_arg1;
+ } else if (args[0] == MGA_ARG2) {
+ *reg |= TD0_color_sel_arg2;
+ } else if (args[0] == MGA_ALPHA) {
+ /* Can't get alpha out by itself */
+ return GL_FALSE;
+ }
+ break;
+ case GL_MODULATE:
+ if (texUnit->CombineScaleShiftRGB == 1) {
+ *reg |= TD0_color_modbright_2x;
+ } else if (texUnit->CombineScaleShiftRGB == 2) {
+ *reg |= TD0_color_modbright_4x;
+ }
+
+ *reg |= TD0_color_sel_mul;
+
+ if (args[0] == MGA_ALPHA || args[1] == MGA_ALPHA) {
+ if (args[0] == MGA_ARG1 || args[1] == MGA_ARG1) {
+ *reg |= TD0_color_arg2mul_alpha2;
+ } else if (args[0] == MGA_ARG2 || args[1] == MGA_ARG2) {
+ *reg |= TD0_color_arg1mul_alpha1;
+ }
+ }
+ break;
+ case GL_ADD_SIGNED:
+ *reg |= TD0_color_addbias_enable;
+ /* fallthrough */
+ case GL_ADD:
+ if (args[0] == MGA_ALPHA || args[1] == MGA_ALPHA){
+ /* Can't get alpha to the adder */
+ return GL_FALSE;
+ }
+ if (texUnit->CombineScaleShiftRGB == 1) {
+ *reg |= TD0_color_add2x_enable;
+ } else if (texUnit->CombineScaleShiftRGB == 2) {
+ return GL_FALSE;
+ }
+
+ *reg |= (TD0_color_add_add |
+ TD0_color_sel_add);
+ break;
+ case GL_INTERPOLATE:
+ if (args[2] != MGA_ALPHA) {
+ /* Only alpha can function as Arg2 */
+ return GL_FALSE;
+ }
+ if (texUnit->CombineScaleShiftRGB == 1) {
+ *reg |= TD0_color_add2x_enable;
+ } else if (texUnit->CombineScaleShiftRGB == 2) {
+ return GL_FALSE;
+ }
+
+ *reg |= (TD0_color_arg1mul_alpha1 |
+ TD0_color_blend_enable |
+ TD0_color_arg1add_mulout |
+ TD0_color_arg2add_mulout |
+ TD0_color_add_add |
+ TD0_color_sel_add);
+
+ /* Have to do this with xor since GL_ONE_MINUS_SRC_ALPHA may have
+ * already touched this bit.
+ */
+ *reg ^= TD0_color_alpha1inv_enable;
+
+ if (args[0] == MGA_ARG2) {
+ /* Swap arguments */
+ *reg ^= (TD0_color_arg1mul_alpha1 |
+ TD0_color_arg2mul_alpha2 |
+ TD0_color_alpha1inv_enable |
+ TD0_color_alpha2inv_enable);
+ }
+
+ if (ctx->Texture._EnabledUnits != 0x03) {
+ /* Linear blending mode needs dualtex enabled */
+ *(reg+1) = (TD0_color_arg2_prevstage |
+ TD0_color_sel_arg2 |
+ TD0_alpha_arg2_prevstage |
+ TD0_alpha_sel_arg2);
+ mmesa->dualtex_env = GL_TRUE;
+ }
+ break;
+ case GL_SUBTRACT:
+ if (args[0] == MGA_ALPHA || args[1] == MGA_ALPHA) {
+ /* Can't get alpha to the adder */
+ return GL_FALSE;
+ }
+ if (texUnit->CombineScaleShiftRGB == 1) {
+ *reg |= TD0_color_add2x_enable;
+ } else if (texUnit->CombineScaleShiftRGB == 2) {
+ return GL_FALSE;
+ }
+
+ *reg |= (TD0_color_add_sub |
+ TD0_color_sel_add);
+
+ if (args[0] == MGA_ARG2) {
+ /* Swap arguments */
+ *reg ^= (TD0_color_arg1_inv_enable |
+ TD0_color_arg2_inv_enable);
+ }
+ break;
+ case GL_MODULATE_SIGNED_ADD_ATI:
+ *reg |= TD0_color_addbias_enable;
+ /* fallthrough */
+ case GL_MODULATE_ADD_ATI:
+ if (args[1] == MGA_ALPHA) {
+ /* Can't get alpha to the adder */
+ return GL_FALSE;
+ }
+ if (texUnit->CombineScaleShiftRGB == 1) {
+ *reg |= TD0_color_add2x_enable;
+ } else if (texUnit->CombineScaleShiftRGB == 2) {
+ return GL_FALSE;
+ }
+
+ *reg |= (TD0_color_add_add |
+ TD0_color_sel_add);
+
+ if (args[1] == args[0] || args[1] == args[2]) {
+ *reg |= TD0_color_arg1add_mulout;
+ if (args[0] == MGA_ALPHA || args[2] == MGA_ALPHA)
+ *reg |= TD0_color_arg1mul_alpha1;
+
+ if (args[1] == MGA_ARG1) {
+ /* Swap adder arguments */
+ *reg ^= (TD0_color_arg1add_mulout |
+ TD0_color_arg2add_mulout);
+ if (args[0] == MGA_ALPHA || args[2] == MGA_ALPHA) {
+ /* Swap multiplier arguments */
+ *reg ^= (TD0_color_arg1mul_alpha1 |
+ TD0_color_arg2mul_alpha2);
+ }
+ }
+ } else {
+ *reg |= (TD0_color_arg2mul_alpha2 |
+ TD0_color_arg1add_mulout);
+
+ if (args[1] == MGA_ARG1) {
+ /* Swap arguments */
+ *reg ^= (TD0_color_arg1mul_alpha1 |
+ TD0_color_arg2mul_alpha2 |
+ TD0_color_arg1add_mulout |
+ TD0_color_arg2add_mulout);
+ }
+ }
+ break;
+ case GL_MODULATE_SUBTRACT_ATI:
+ if (args[1] != MGA_ARG2) {
+ /* Can't swap arguments */
+ return GL_FALSE;
+ }
+ if (texUnit->CombineScaleShiftRGB == 1) {
+ *reg |= TD0_color_add2x_enable;
+ } else if (texUnit->CombineScaleShiftRGB == 2) {
+ return GL_FALSE;
+ }
+
+ *reg |= (TD0_color_add_sub |
+ TD0_color_sel_add);
+
+ if (args[1] == args[0] || args[1] == args[2]) {
+ *reg |= TD0_color_arg1add_mulout;
+ if (args[0] == MGA_ALPHA || args[2] == MGA_ALPHA)
+ *reg |= TD0_color_arg1mul_alpha1;
+ } else {
+ *reg |= (TD0_color_arg2mul_alpha2 |
+ TD0_color_arg1add_mulout);
+ }
+ break;
+ }
+
+
+ /* ALPHA */
+ for (i = 0; i < 2; i++) {
+ arg1[i] = 0;
+ arg2[i] = 0;
+ }
+
+ for (i = 0; i < numAlphaArgs; i++) {
+ switch (texUnit->CombineSourceA[i]) {
+ case GL_TEXTURE:
+ arg1[i] |= 0;
+ arg2[i] |= ARG_DISABLE;
+ break;
+ case GL_TEXTURE0:
+ if (source == 0) {
+ arg1[i] |= 0;
+ arg2[i] |= ARG_DISABLE;
+ } else {
+ if (ctx->Texture._EnabledUnits != 0x03) {
+ /* disable texturing */
+ mmesa->setup.dwgctl &= DC_opcod_MASK;
+ mmesa->setup.dwgctl |= DC_opcod_trap;
+ mmesa->hw.alpha_sel = AC_alphasel_diffused;
+ /* return GL_TRUE since we don't need a fallback */
+ return GL_TRUE;
+ }
+ arg1[i] |= ARG_DISABLE;
+ arg2[i] |= TD0_alpha_arg2_prevtex;
+ }
+ break;
+ case GL_TEXTURE1:
+ if (source == 0) {
+ if (ctx->Texture._EnabledUnits != 0x03) {
+ /* disable texturing */
+ mmesa->setup.dwgctl &= DC_opcod_MASK;
+ mmesa->setup.dwgctl |= DC_opcod_trap;
+ mmesa->hw.alpha_sel = AC_alphasel_diffused;
+ /* return GL_TRUE since we don't need a fallback */
+ return GL_TRUE;
+ }
+ arg1[i] |= ARG_DISABLE;
+ /* G400 specs (TDUALSTAGE0) */
+ arg2[i] |= TD0_alpha_arg2_prevstage;
+ } else {
+ arg1[i] |= 0;
+ arg2[i] |= ARG_DISABLE;
+ }
+ break;
+ case GL_CONSTANT:
+ arg1[i] |= ARG_DISABLE;
+ arg2[i] |= TD0_alpha_arg2_fcol;
+ break;
+ case GL_PRIMARY_COLOR:
+ arg1[i] |= ARG_DISABLE;
+ /* G400 specs (TDUALSTAGE1) */
+ if (unit == 0 || (mmesa->setup.tdualstage0 &
+ ((TD0_color_sel_mul & TD0_color_sel_add) |
+ (TD0_alpha_sel_mul & TD0_alpha_sel_add)))) {
+ arg2[i] |= TD0_alpha_arg2_diffuse;
+ } else {
+ arg2[i] |= ARG_DISABLE;
+ }
+ break;
+ case GL_PREVIOUS:
+ arg1[i] |= ARG_DISABLE;
+ if (unit == 0) {
+ arg2[i] |= TD0_alpha_arg2_diffuse;
+ } else {
+ arg2[i] |= TD0_alpha_arg2_prevstage;
+ }
+ break;
+ default:
+ return GL_FALSE;
+ }
+
+ switch (texUnit->CombineOperandA[i]) {
+ case GL_SRC_ALPHA:
+ arg1[i] |= 0;
+ arg2[i] |= 0;
+ break;
+ case GL_ONE_MINUS_SRC_ALPHA:
+ arg1[i] |= TD0_alpha_arg1_inv_enable;
+ arg2[i] |= TD0_alpha_arg2_inv_enable;
+ break;
+ }
+ }
+
+ /* Find a working combo of arg1 and arg2 */
+ if ((arg1[0] | arg2[1]) != ARG_DISABLE) {
+ *reg |= arg1[0] | arg2[1];
+ args[0] = MGA_ARG1; args[1] = MGA_ARG2;
+ } else
+ if ((arg1[1] | arg2[0]) != ARG_DISABLE) {
+ *reg |= arg1[1] | arg2[0];
+ args[0] = MGA_ARG2; args[1] = MGA_ARG1;
+ } else {
+ /* nothing suitable */
+ return GL_FALSE;
+ }
+
+ switch (texUnit->CombineModeA) {
+ case GL_REPLACE:
+ if (texUnit->CombineScaleShiftA) {
+ return GL_FALSE;
+ }
+
+ if (args[0] == MGA_ARG1){
+ *reg |= TD0_alpha_sel_arg1;
+ } else if (args[0] == MGA_ARG2) {
+ *reg |= TD0_alpha_sel_arg2;
+ }
+ break;
+ case GL_MODULATE:
+ if (texUnit->CombineScaleShiftA == 1) {
+ *reg |= TD0_alpha_modbright_2x;
+ } else if (texUnit->CombineScaleShiftA == 2) {
+ *reg |= TD0_alpha_modbright_4x;
+ }
+
+ *reg |= TD0_alpha_sel_mul;
+ break;
+ case GL_ADD_SIGNED:
+ *reg |= TD0_alpha_addbias_enable;
+ /* fallthrough */
+ case GL_ADD:
+ if (texUnit->CombineScaleShiftA == 1) {
+ *reg |= TD0_alpha_add2x_enable;
+ } else if (texUnit->CombineScaleShiftA == 2) {
+ return GL_FALSE;
+ }
+
+ *reg |= (TD0_alpha_add_enable |
+ TD0_alpha_sel_add);
+ break;
+ case GL_SUBTRACT:
+ if (texUnit->CombineScaleShiftA == 1) {
+ *reg |= TD0_alpha_add2x_enable;
+ } else if (texUnit->CombineScaleShiftA == 2) {
+ return GL_FALSE;
+ }
+
+ *reg |= (TD0_alpha_add_disable |
+ TD0_alpha_sel_add);
+
+ if (args[0] == MGA_ARG2) {
+ /* Swap arguments */
+ *reg ^= (TD0_alpha_arg1_inv_enable |
+ TD0_alpha_arg2_inv_enable);
+ }
+ break;
+ }
+
+ return GL_TRUE;
+}
+
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-06 13:52:02 +0000